diff --git a/doc/services/portability/posix.rst b/doc/services/portability/posix.rst
index 0b6e0f54da9..fb06cba1c75 100644
--- a/doc/services/portability/posix.rst
+++ b/doc/services/portability/posix.rst
@@ -380,7 +380,7 @@ required for error and event handling.
     sigdelset(),yes
     sigemptyset(),yes
     sigfillset(),yes
-    igismember(),
+    sigismember(),yes
     signal(),
     sigpending(),
     sigprocmask(),
diff --git a/include/zephyr/posix/signal.h b/include/zephyr/posix/signal.h
index 462bff8ce4d..8c509954edd 100644
--- a/include/zephyr/posix/signal.h
+++ b/include/zephyr/posix/signal.h
@@ -59,6 +59,7 @@ int sigemptyset(sigset_t *set);
 int sigfillset(sigset_t *set);
 int sigaddset(sigset_t *set, int signo);
 int sigdelset(sigset_t *set, int signo);
+int sigismember(const sigset_t *set, int signo);
 #endif /* CONFIG_POSIX_SIGNAL */
 
 #ifndef SIGEV_NONE
diff --git a/lib/posix/signal.c b/lib/posix/signal.c
index d20557b3fc1..165d9aa9dbc 100644
--- a/lib/posix/signal.c
+++ b/lib/posix/signal.c
@@ -58,3 +58,13 @@ int sigdelset(sigset_t *set, int signo)
 
 	return 0;
 }
+
+int sigismember(const sigset_t *set, int signo)
+{
+	if (!signo_valid(signo)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	return 1 & (set->sig[SIGNO_WORD_IDX(signo)] >> SIGNO_WORD_BIT(signo));
+}
diff --git a/tests/posix/common/src/signal.c b/tests/posix/common/src/signal.c
index afc0fb9e60b..90fb001bc5b 100644
--- a/tests/posix/common/src/signal.c
+++ b/tests/posix/common/src/signal.c
@@ -157,3 +157,38 @@ ZTEST(posix_apis, test_signal_delset)
 			      ARRAY_SIZE(set.sig) - 1, set.sig[i], target.sig[i]);
 	}
 }
+
+ZTEST(posix_apis, test_signal_ismember_oor)
+{
+	sigset_t set = {0};
+
+	zassert_equal(sigismember(&set, -1), -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+
+	zassert_equal(sigismember(&set, 0), -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+
+	zassert_equal(sigismember(&set, _NSIG), -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+}
+
+ZTEST(posix_apis, test_signal_ismember)
+{
+	sigset_t set = (sigset_t){0};
+
+#ifdef CONFIG_64BIT
+	set.sig[0] = BIT(SIGHUP) | BIT(SIGSYS) | BIT(SIGRTMIN);
+#else /* 32BIT */
+	set.sig[0] = BIT(SIGHUP) | BIT(SIGSYS);
+	set.sig[1] = BIT((SIGRTMIN)-BITS_PER_LONG);
+#endif
+	WRITE_BIT(set.sig[SIGRTMAX / BITS_PER_LONG], SIGRTMAX % BITS_PER_LONG, 1);
+
+	zassert_equal(sigismember(&set, SIGHUP), 1, "%s expected to be member", "SIGHUP");
+	zassert_equal(sigismember(&set, SIGSYS), 1, "%s expected to be member", "SIGSYS");
+	zassert_equal(sigismember(&set, SIGRTMIN), 1, "%s expected to be member", "SIGRTMIN");
+	zassert_equal(sigismember(&set, SIGRTMAX), 1, "%s expected to be member", "SIGRTMAX");
+
+	zassert_equal(sigismember(&set, SIGKILL), 0, "%s not expected to be member", "SIGKILL");
+	zassert_equal(sigismember(&set, SIGTERM), 0, "%s not expected to be member", "SIGTERM");
+}
diff --git a/tests/posix/headers/src/signal_h.c b/tests/posix/headers/src/signal_h.c
index 34703c0b2c0..5a78c0ec0a7 100644
--- a/tests/posix/headers/src/signal_h.c
+++ b/tests/posix/headers/src/signal_h.c
@@ -162,6 +162,7 @@ ZTEST(posix_headers, test_signal_h)
 	zassert_not_null(sigfillset);
 	zassert_not_null(sigaddset);
 	zassert_not_null(sigdelset);
+	zassert_not_null(sigismember);
 #endif /* CONFIG_POSIX_SIGNAL */
 
 	if (IS_ENABLED(CONFIG_POSIX_API)) {
@@ -177,7 +178,6 @@ ZTEST(posix_headers, test_signal_h)
 		/* zassert_not_null(sighold); */ /* not implemented */
 		/* zassert_not_null(sigignore); */ /* not implemented */
 		/* zassert_not_null(siginterrupt); */ /* not implemented */
-		/* zassert_not_null(sigismember); */ /* not implemented */
 		/* zassert_not_null(signal); */ /* not implemented */
 		/* zassert_not_null(sigpause); */ /* not implemented */
 		/* zassert_not_null(sigpending); */ /* not implemented */