diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4cc86184..4f053b8b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,8 @@
 * Swapped setup approach to the modern `pyproject.toml` standard. [#507](https://github.com/NeurodataWithoutBorders/nwbinspector/pull/507)
 * Added complete annotation typing and integrated Mypy into pre-commit. [#520](https://github.com/NeurodataWithoutBorders/nwbinspector/pull/520)
 
+### Fixes
+* Fixed incorrect error message for OptogeneticStimulusSite. [#524](https://github.com/NeurodataWithoutBorders/nwbinspector/pull/524)
 
 
 # v0.5.2
diff --git a/src/nwbinspector/checks/_ogen.py b/src/nwbinspector/checks/_ogen.py
index 27e8a08c..7981bd65 100644
--- a/src/nwbinspector/checks/_ogen.py
+++ b/src/nwbinspector/checks/_ogen.py
@@ -16,4 +16,4 @@ def check_optogenetic_stimulus_site_has_optogenetic_series(
             if obj.site == ogen_site:
                 return None
 
-    return InspectorMessage(message="OptogeneticStimulusSite is not referenced by any OptogeneticStimulusSite.")
+    return InspectorMessage(message="OptogeneticStimulusSite is not referenced by any OptogeneticSeries.")
diff --git a/tests/unit_tests/test_ogen.py b/tests/unit_tests/test_ogen.py
index 70563ffe..42979e34 100644
--- a/tests/unit_tests/test_ogen.py
+++ b/tests/unit_tests/test_ogen.py
@@ -39,5 +39,5 @@ def test_check_pass(self):
     def test_check_triggered(self):
         assert (
             check_optogenetic_stimulus_site_has_optogenetic_series(self.ogen_site).message
-            == "OptogeneticStimulusSite is not referenced by any OptogeneticStimulusSite."
+            == "OptogeneticStimulusSite is not referenced by any OptogeneticSeries."
         )