diff --git a/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_posix.conf b/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_posix.conf
deleted file mode 100644
index eb56d825c96..00000000000
--- a/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_posix.conf
+++ /dev/null
@@ -1 +0,0 @@
-CONFIG_NATIVE_POSIX_SLOWDOWN_TO_REAL_TIME=y
diff --git a/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_sim.conf b/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_sim.conf
new file mode 100644
index 00000000000..0843e94acbd
--- /dev/null
+++ b/tests/net/lib/lwm2m/lwm2m_rd_client/boards/native_sim.conf
@@ -0,0 +1 @@
+CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME=y
diff --git a/tests/net/lib/lwm2m/lwm2m_rd_client/src/main.c b/tests/net/lib/lwm2m/lwm2m_rd_client/src/main.c
index 03d0dce7f49..931f6f15904 100644
--- a/tests/net/lib/lwm2m/lwm2m_rd_client/src/main.c
+++ b/tests/net/lib/lwm2m/lwm2m_rd_client/src/main.c
@@ -9,8 +9,8 @@
 #include <zephyr/fff.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/ztest.h>
-#if defined(CONFIG_NATIVE_POSIX_SLOWDOWN_TO_REAL_TIME)
-#include "timer_model.h"
+#if defined(CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME)
+#include "nsi_timer_model.h"
 #endif
 #include <lwm2m_rd_client.h>
 
@@ -141,7 +141,7 @@ static void lwm2m_observe_cb(enum lwm2m_observe_event event, struct lwm2m_obj_pa
 
 static void my_suite_before(void *data)
 {
-#if defined(CONFIG_NATIVE_POSIX_SLOWDOWN_TO_REAL_TIME)
+#if defined(CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME)
 	/* It is enough that some slow-down is happening on sleeps, it does not have to be
 	 * real time
 	 */
diff --git a/tests/net/lib/lwm2m/lwm2m_rd_client/testcase.yaml b/tests/net/lib/lwm2m/lwm2m_rd_client/testcase.yaml
index 80c5bee1131..df49b3c7342 100644
--- a/tests/net/lib/lwm2m/lwm2m_rd_client/testcase.yaml
+++ b/tests/net/lib/lwm2m/lwm2m_rd_client/testcase.yaml
@@ -5,7 +5,7 @@ common:
     - lwm2m
     - net
   platform_allow:
-    - native_posix
+    - native_sim
 tests:
   net.lwm2m.lwm2m_rd_client:
     extra_args: EXTRA_CFLAGS=""