diff --git a/src/amf/amf-sm.c b/src/amf/amf-sm.c
index 899d04c12..2ff02482d 100644
--- a/src/amf/amf-sm.c
+++ b/src/amf/amf-sm.c
@@ -209,11 +209,10 @@ void amf_state_operational(ogs_fsm_t *s, amf_event_t *e)
                         stream, &sbi_message);
                 break;
 
-            /* TODO */
-#if 0
             CASE(OGS_SBI_RESOURCE_NAME_DEREG_NOTIFY)
+                amf_namf_callback_handle_dereg_notify(stream, &sbi_message);
                 break;
-#endif
+
             CASE(OGS_SBI_RESOURCE_NAME_AM_POLICY_NOTIFY)
                 ogs_assert(true == ogs_sbi_send_http_status_no_content(stream));
                 break;
diff --git a/src/amf/context.h b/src/amf/context.h
index 16fdb38f8..c5426f2ff 100644
--- a/src/amf/context.h
+++ b/src/amf/context.h
@@ -408,6 +408,9 @@ struct amf_ue_s {
         long cause;
     } handover;
 
+    /* Network Initiated De-Registration */
+    bool network_initiated_de_reg;
+
     ogs_list_t      sess_list;
 };
 
diff --git a/src/amf/gmm-build.c b/src/amf/gmm-build.c
index 5ec36ca3c..f57fd96c9 100644
--- a/src/amf/gmm-build.c
+++ b/src/amf/gmm-build.c
@@ -276,6 +276,35 @@ ogs_pkbuf_t *gmm_build_de_registration_accept(amf_ue_t *amf_ue)
     return nas_5gs_security_encode(amf_ue, &message);
 }
 
+ogs_pkbuf_t *gmm_build_de_registration_request(amf_ue_t *amf_ue)
+{
+    ogs_nas_5gs_message_t message;
+    ogs_nas_5gs_deregistration_request_to_ue_t *dereg_req =
+        &message.gmm.deregistration_request_to_ue;
+
+    ogs_assert(amf_ue);
+
+    memset(&message, 0, sizeof(message));
+    message.h.security_header_type =
+        OGS_NAS_SECURITY_HEADER_INTEGRITY_PROTECTED_AND_CIPHERED;
+    message.h.extended_protocol_discriminator =
+        OGS_NAS_EXTENDED_PROTOCOL_DISCRIMINATOR_5GMM;
+
+    message.gmm.h.extended_protocol_discriminator =
+        OGS_NAS_EXTENDED_PROTOCOL_DISCRIMINATOR_5GMM;
+    message.gmm.h.message_type = OGS_NAS_5GS_DEREGISTRATION_REQUEST_TO_UE;
+
+    dereg_req->de_registration_type.switch_off = 1;
+    dereg_req->de_registration_type.re_registration_required = 0;
+    dereg_req->de_registration_type.access_type = OGS_ACCESS_TYPE_3GPP;
+
+    dereg_req->presencemask |=
+        OGS_NAS_5GS_DEREGISTRATION_REQUEST_TO_UE_5GMM_CAUSE_PRESENT;
+    dereg_req->gmm_cause = OGS_5GMM_CAUSE_5GS_SERVICES_NOT_ALLOWED;
+
+    return nas_5gs_security_encode(amf_ue, &message);
+}
+
 ogs_pkbuf_t *gmm_build_identity_request(amf_ue_t *amf_ue)
 {
     ogs_nas_5gs_message_t message;
diff --git a/src/amf/gmm-build.h b/src/amf/gmm-build.h
index dba3034b0..d5185fcf6 100644
--- a/src/amf/gmm-build.h
+++ b/src/amf/gmm-build.h
@@ -34,6 +34,7 @@ ogs_pkbuf_t *gmm_build_service_reject(
         amf_ue_t *amf_ue, ogs_nas_5gmm_cause_t gmm_cause);
 
 ogs_pkbuf_t *gmm_build_de_registration_accept(amf_ue_t *amf_ue);
+ogs_pkbuf_t *gmm_build_de_registration_request(amf_ue_t *amf_ue);
 
 ogs_pkbuf_t *gmm_build_identity_request(amf_ue_t *amf_ue);
 ogs_pkbuf_t *gmm_build_security_mode_command(amf_ue_t *amf_ue);
diff --git a/src/amf/gmm-sm.c b/src/amf/gmm-sm.c
index 93ee9234a..20ab49284 100644
--- a/src/amf/gmm-sm.c
+++ b/src/amf/gmm-sm.c
@@ -286,6 +286,21 @@ static void common_register_state(ogs_fsm_t *s, amf_event_t *e)
             OGS_FSM_TRAN(s, &gmm_state_de_registered);
             break;
 
+        case OGS_NAS_5GS_DEREGISTRATION_ACCEPT_TO_UE:
+            ogs_info("[%s] Deregistration accept", amf_ue->supi);
+            CLEAR_AMF_UE_TIMER(amf_ue->t3522);
+
+            /* De-associate NG with NAS/EMM */
+            ran_ue_deassociate(amf_ue->ran_ue);
+
+            ogs_assert(OGS_OK ==
+                ngap_send_ran_ue_context_release_command(amf_ue->ran_ue,
+                    NGAP_Cause_PR_misc, NGAP_CauseMisc_om_intervention,
+                    NGAP_UE_CTX_REL_NG_CONTEXT_REMOVE, 0));
+
+            OGS_FSM_TRAN(s, &gmm_state_de_registered);
+            break;
+
         case OGS_NAS_5GS_CONFIGURATION_UPDATE_COMPLETE:
             ogs_debug("[%s] Configuration update complete", amf_ue->supi);
 
@@ -414,6 +429,20 @@ static void common_register_state(ogs_fsm_t *s, amf_event_t *e)
             }
             break;
 
+        case AMF_TIMER_T3522:
+            if (amf_ue->t3522.retry_count >=
+                    amf_timer_cfg(AMF_TIMER_T3522)->max_count) {
+                ogs_warn("Retransmission of Deregistration-Request failed. "
+                        "Stop retransmission");
+                CLEAR_AMF_UE_TIMER(amf_ue->t3522);
+                OGS_FSM_TRAN(&amf_ue->t3522, &gmm_state_exception);
+            } else {
+                amf_ue->t3522.retry_count++;
+                ogs_assert(OGS_OK ==
+                    nas_5gs_send_de_registration_request(amf_ue));
+            }
+            break;
+
         default:
             ogs_error("Unknown timer[%s:%d]",
                     amf_timer_get_name(e->timer_id), e->timer_id);
@@ -432,8 +461,10 @@ static void common_register_state(ogs_fsm_t *s, amf_event_t *e)
             CASE(OGS_SBI_RESOURCE_NAME_POLICIES)
                 SWITCH(sbi_message->h.method)
                 CASE(OGS_SBI_HTTP_METHOD_DELETE)
-                    ogs_assert(OGS_OK ==
-                        nas_5gs_send_de_registration_accept(amf_ue));
+
+                    if (!amf_ue->network_initiated_de_reg)
+                        ogs_assert(OGS_OK ==
+                            nas_5gs_send_de_registration_accept(amf_ue));
 
                     PCF_AM_POLICY_CLEAR(amf_ue);
                     break;
diff --git a/src/amf/namf-handler.c b/src/amf/namf-handler.c
index 08ae9afe6..8ed4cea30 100644
--- a/src/amf/namf-handler.c
+++ b/src/amf/namf-handler.c
@@ -508,3 +508,92 @@ cleanup:
 
     return OGS_OK;
 }
+
+int amf_namf_callback_handle_dereg_notify(
+        ogs_sbi_stream_t *stream, ogs_sbi_message_t *recvmsg)
+{
+    int status = OGS_SBI_HTTP_STATUS_NO_CONTENT;
+
+    amf_ue_t *amf_ue = NULL;
+
+    ogs_sbi_message_t sendmsg;
+    ogs_sbi_response_t *response = NULL;
+
+    OpenAPI_deregistration_data_t *DeregistrationData;
+
+    ogs_assert(stream);
+    ogs_assert(recvmsg);
+
+    if (!recvmsg->h.resource.component[0]) {
+        status = OGS_SBI_HTTP_STATUS_BAD_REQUEST;
+        ogs_error("No SUPI");
+        goto cleanup;
+    }
+
+    amf_ue = amf_ue_find_by_supi(recvmsg->h.resource.component[0]);
+    if (!amf_ue) {
+        status = OGS_SBI_HTTP_STATUS_NOT_FOUND;
+        ogs_error("Cannot find SUPI [%s]", recvmsg->h.resource.component[0]);
+        goto cleanup;
+    }
+
+    DeregistrationData = recvmsg->DeregistrationData;
+    if (!DeregistrationData) {
+        status = OGS_SBI_HTTP_STATUS_BAD_REQUEST;
+        ogs_error("[%s] No DeregistrationData", amf_ue->supi);
+        goto cleanup;
+    }
+
+    if (DeregistrationData->access_type != OpenAPI_access_type_3GPP_ACCESS)
+    {
+        status = OGS_SBI_HTTP_STATUS_BAD_REQUEST;
+        ogs_error("[%s] Deregistration access type not 3GPP", amf_ue->supi);
+        goto cleanup;
+    }
+
+    ogs_info("Deregistration notify reason: %s:%s:%s",
+        amf_ue->supi,
+        OpenAPI_deregistration_reason_ToString(DeregistrationData->dereg_reason),
+        OpenAPI_access_type_ToString(DeregistrationData->access_type));
+
+    /*
+     * TODO: do not start deregistration if UE has emergency sessions
+     * 4.2.2.3.3
+     * If the UE has established PDU Session associated with emergency service, the AMF shall not initiate
+     * Deregistration procedure. In this case, the AMF performs network requested PDU Session Release for any PDU
+     * session associated with non-emergency service as described in clause 4.3.4.
+     */
+
+
+    if (CM_CONNECTED(amf_ue))
+    {
+        amf_ue->network_initiated_de_reg = true;
+
+        ogs_assert(OGS_OK ==
+            nas_5gs_send_de_registration_request(amf_ue));
+
+            amf_sbi_send_release_all_sessions(
+                amf_ue, AMF_RELEASE_SM_CONTEXT_NO_STATE);
+
+            if (ogs_list_count(&amf_ue->sess_list) == 0)
+                ogs_assert(true ==
+                    amf_ue_sbi_discover_and_send(
+                        OpenAPI_nf_type_PCF, amf_ue,
+                        NULL, amf_npcf_am_policy_control_build_delete));
+
+            OGS_FSM_TRAN(&amf_ue->sm, &gmm_state_de_registered);
+    }
+    else if (CM_IDLE(amf_ue)) {
+        /* TODO: need to page UE */
+        /*ngap_send_paging(amf_ue);*/
+    }
+
+cleanup:
+    memset(&sendmsg, 0, sizeof(sendmsg));
+
+    response = ogs_sbi_build_response(&sendmsg, status);
+    ogs_assert(response);
+    ogs_assert(true == ogs_sbi_server_send_response(stream, response));
+
+    return OGS_OK;
+}
diff --git a/src/amf/namf-handler.h b/src/amf/namf-handler.h
index 11e152991..d529377dd 100644
--- a/src/amf/namf-handler.h
+++ b/src/amf/namf-handler.h
@@ -30,6 +30,8 @@ int amf_namf_comm_handle_n1_n2_message_transfer(
         ogs_sbi_stream_t *stream, ogs_sbi_message_t *recvmsg);
 int amf_namf_callback_handle_sm_context_status(
         ogs_sbi_stream_t *stream, ogs_sbi_message_t *recvmsg);
+int amf_namf_callback_handle_dereg_notify(
+        ogs_sbi_stream_t *stream, ogs_sbi_message_t *recvmsg);
 
 #ifdef __cplusplus
 }
diff --git a/src/amf/nas-path.c b/src/amf/nas-path.c
index d7a287090..4de6c61d7 100644
--- a/src/amf/nas-path.c
+++ b/src/amf/nas-path.c
@@ -276,6 +276,38 @@ int nas_5gs_send_de_registration_accept(amf_ue_t *amf_ue)
     return rv;
 }
 
+int nas_5gs_send_de_registration_request(amf_ue_t *amf_ue)
+{
+    int rv;
+
+    ran_ue_t *ran_ue = NULL;
+    ogs_pkbuf_t *gmmbuf = NULL;
+
+    ogs_assert(amf_ue);
+    ran_ue = ran_ue_cycle(amf_ue->ran_ue);
+    ogs_expect_or_return_val(ran_ue, OGS_ERROR);
+
+    ogs_debug("[%s] De-registration request", amf_ue->supi);
+
+    if (amf_ue->t3522.pkbuf) {
+        gmmbuf = amf_ue->t3522.pkbuf;
+        ogs_expect_or_return_val(gmmbuf, OGS_ERROR);
+    } else {
+        gmmbuf = gmm_build_de_registration_request(amf_ue);
+        ogs_expect_or_return_val(gmmbuf, OGS_ERROR);
+    }
+
+    amf_ue->t3522.pkbuf = ogs_pkbuf_copy(gmmbuf);
+    ogs_expect_or_return_val(amf_ue->t3522.pkbuf, OGS_ERROR);
+    ogs_timer_start(amf_ue->t3522.timer,
+            amf_timer_cfg(AMF_TIMER_T3522)->duration);
+
+    rv = nas_5gs_send_to_downlink_nas_transport(amf_ue, gmmbuf);
+    ogs_expect_or_return_val(rv == OGS_OK, OGS_ERROR);
+
+    return rv;
+}
+
 int nas_5gs_send_identity_request(amf_ue_t *amf_ue)
 {
     int rv;
diff --git a/src/amf/nas-path.h b/src/amf/nas-path.h
index 27f50efd0..40944a07c 100644
--- a/src/amf/nas-path.h
+++ b/src/amf/nas-path.h
@@ -41,6 +41,7 @@ int nas_5gs_send_service_reject(
         amf_ue_t *amf_ue, ogs_nas_5gmm_cause_t gmm_cause);
 
 int nas_5gs_send_de_registration_accept(amf_ue_t *amf_ue);
+int nas_5gs_send_de_registration_request(amf_ue_t *amf_ue);
 
 int nas_5gs_send_identity_request(amf_ue_t *amf_ue);