diff --git a/src/test/fuzz/fuzz.cpp b/src/test/fuzz/fuzz.cpp
index e4e4723c74..eda5ff4cc6 100644
--- a/src/test/fuzz/fuzz.cpp
+++ b/src/test/fuzz/fuzz.cpp
@@ -78,11 +78,13 @@ void FuzzFrameworkRegisterTarget(std::string_view name, TypeTestOneInput target,
 
 static std::string_view g_fuzz_target;
 static const TypeTestOneInput* g_test_one_input{nullptr};
+bool g_ever_used_g_mocktime{false};
 
 inline void test_one_input(FuzzBufferType buffer)
 {
     CheckGlobals check{};
     (*Assert(g_test_one_input))(buffer);
+    g_ever_used_g_mocktime|= g_used_mocktime;
 }
 
 const std::function<std::string()> G_TEST_GET_FULL_NAME{[]{
@@ -274,6 +276,9 @@ int main(int argc, char** argv)
     }
     const auto end_time{Now<SteadySeconds>()};
     std::cout << g_fuzz_target << ": succeeded against " << tested << " files in " << count_seconds(end_time - start_time) << "s." << std::endl;
+    if (tested && !g_ever_used_g_mocktime && g_set_mocktime) {
+        Assert(false); // remove unused SetMockTime()?
+    }
 #endif
     return 0;
 }
diff --git a/src/test/fuzz/util/check_globals.cpp b/src/test/fuzz/util/check_globals.cpp
index f91a965afc..76d62fa3ca 100644
--- a/src/test/fuzz/util/check_globals.cpp
+++ b/src/test/fuzz/util/check_globals.cpp
@@ -17,6 +17,8 @@ struct CheckGlobalsImpl {
     {
         g_used_g_prng = false;
         g_seeded_g_prng_zero = false;
+        g_set_mocktime= false;
+        g_used_mocktime=false;
         g_used_system_time = false;
         SetMockTime(0s);
     }
diff --git a/src/test/fuzz/util/check_globals.h b/src/test/fuzz/util/check_globals.h
index 12d39c2daf..798a9ba506 100644
--- a/src/test/fuzz/util/check_globals.h
+++ b/src/test/fuzz/util/check_globals.h
@@ -10,6 +10,8 @@
 #include <optional>
 #include <string>
 
+extern std::atomic<bool> g_set_mocktime;
+extern std::atomic<bool> g_used_mocktime;
 extern std::atomic<bool> g_used_system_time;
 
 struct CheckGlobalsImpl;
diff --git a/src/util/time.cpp b/src/util/time.cpp
index 00f0f47392..f8f1eb5504 100644
--- a/src/util/time.cpp
+++ b/src/util/time.cpp
@@ -20,6 +20,8 @@
 void UninterruptibleSleep(const std::chrono::microseconds& n) { std::this_thread::sleep_for(n); }
 
 static std::atomic<std::chrono::seconds> g_mock_time{}; //!< For testing
+std::atomic<bool> g_set_mocktime{false};
+std::atomic<bool> g_used_mocktime{false};
 std::atomic<bool> g_used_system_time{false};
 
 NodeClock::time_point NodeClock::now() noexcept
@@ -27,6 +29,8 @@ NodeClock::time_point NodeClock::now() noexcept
     const auto mocktime{g_mock_time.load(std::memory_order_relaxed)};
     if (!mocktime.count()) {
         g_used_system_time = true;
+    }else{
+    g_used_mocktime=true;
     }
     const auto ret{
         mocktime.count() ?
@@ -40,6 +44,7 @@ void SetMockTime(int64_t nMockTimeIn) { SetMockTime(std::chrono::seconds{nMockTi
 void SetMockTime(std::chrono::seconds mock_time_in)
 {
     Assert(mock_time_in >= 0s);
+    g_set_mocktime=true;
     g_mock_time.store(mock_time_in, std::memory_order_relaxed);
 }