diff --git a/.changeset/two-bars-warn.md b/.changeset/two-bars-warn.md
new file mode 100644
index 0000000000..beef36201f
--- /dev/null
+++ b/.changeset/two-bars-warn.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-catalog': patch
+---
+
+Fixed bug in EntityLayout that caused wiping existing query parameters when opening the InspectEntityDialog.
diff --git a/plugins/catalog/src/components/EntityLayout/EntityLayout.tsx b/plugins/catalog/src/components/EntityLayout/EntityLayout.tsx
index bae1f7bd0c..65f904c285 100644
--- a/plugins/catalog/src/components/EntityLayout/EntityLayout.tsx
+++ b/plugins/catalog/src/components/EntityLayout/EntityLayout.tsx
@@ -361,7 +361,13 @@ export const EntityLayout = (props: EntityLayoutProps) => {
               UNSTABLE_extraContextMenuItems={UNSTABLE_extraContextMenuItems}
               UNSTABLE_contextMenuOptions={UNSTABLE_contextMenuOptions}
               onUnregisterEntity={() => setConfirmationDialogOpen(true)}
-              onInspectEntity={() => setSearchParams('inspect')}
+              onInspectEntity={() => {
+                setSearchParams(prev => {
+                  const newParams = new URLSearchParams(prev);
+                  newParams.set('inspect', '');
+                  return newParams;
+                });
+              }}
             />
           </>
         )}
@@ -401,9 +407,21 @@ export const EntityLayout = (props: EntityLayoutProps) => {
               typeof InspectEntityDialog
             >['initialTab']) || undefined
           }
-          onSelect={newTab => setSearchParams(`inspect=${newTab}`)}
+          onSelect={newTab =>
+            setSearchParams(prev => {
+              const newParams = new URLSearchParams(prev);
+              newParams.set('inspect', newTab);
+              return newParams;
+            })
+          }
           open
-          onClose={() => setSearchParams()}
+          onClose={() =>
+            setSearchParams(prev => {
+              const newParams = new URLSearchParams(prev);
+              newParams.delete('inspect');
+              return newParams;
+            })
+          }
         />
       )}