diff --git a/src/test/test_funktionen.c b/src/test/test_funktionen.c
index 39eb3d5..97e9ceb 100644
--- a/src/test/test_funktionen.c
+++ b/src/test/test_funktionen.c
@@ -43,4 +43,10 @@ void test_logarithm(void) {
     // Add more test cases for different inputs and expected outputs
 }
 
+void test_naturalLogarithm(void) {
+    float result = naturalLogarithm(100.0);
+    TEST_ASSERT_FLOAT_WITHIN(0.000001, 4.60517, result);
+    // Add more test cases for different inputs and expected outputs
+}
+
 #endif
\ No newline at end of file