diff --git a/crates/oxc_linter/src/lib.rs b/crates/oxc_linter/src/lib.rs
index b0482861f7ac1..bf751b287f7f0 100644
--- a/crates/oxc_linter/src/lib.rs
+++ b/crates/oxc_linter/src/lib.rs
@@ -274,9 +274,18 @@ impl Linter {
                                 // TODO: `error` isn't right, we need to get the severity from `external_rules`
                                 OxcDiagnostic::error(diagnostic.message)
                                     .with_label(Span::new(diagnostic.loc.start, diagnostic.loc.end))
-                                    .with_error_code(
-                                        plugin_name.to_string(),
-                                        rule_name.to_string(),
+                                    .with_error_code(plugin_name.to_string(), rule_name.to_string())
+                                    .with_severity(
+                                        (*external_rules
+                                            .iter()
+                                            .find(|(rule_id, _)| {
+                                                rule_id.raw() == diagnostic.external_rule_id
+                                            })
+                                            .map(|(_, severity)| severity)
+                                            .expect(
+                                                "external rule must exist when resolving severity",
+                                            ))
+                                        .into(),
                                     ),
                                 PossibleFixes::None,
                             ));
diff --git a/napi/oxlint2/test/__snapshots__/e2e.test.ts.snap b/napi/oxlint2/test/__snapshots__/e2e.test.ts.snap
index e691005ab1d47..8f312d0978265 100644
--- a/napi/oxlint2/test/__snapshots__/e2e.test.ts.snap
+++ b/napi/oxlint2/test/__snapshots__/e2e.test.ts.snap
@@ -336,3 +336,22 @@ exports[`oxlint2 CLI > should report an error if a rule is not found within a cu
   x Rule 'unknown-rule' not found in plugin 'basic-custom-plugin'
 "
 `;
+
+exports[`oxlint2 CLI > should report the correct severity when using a custom plugin 1`] = `
+"
+  ! ]8;;https://oxc.rs/docs/guide/usage/linter/rules/eslint/no-debugger.html\\eslint(no-debugger)]8;;\\: \`debugger\` statement is not allowed
+   ,-[index.js:1:1]
+ 1 | debugger;
+   : ^^^^^^^^^
+   \`----
+  help: Remove the debugger statement
+
+  ! basic-custom-plugin(no-debugger): Unexpected Debugger Statement
+   ,-[index.js:1:1]
+ 1 | debugger;
+   : ^^^^^^^^^
+   \`----
+
+Found 2 warnings and 0 errors.
+Finished in Xms on 1 file using X threads."
+`;
diff --git a/napi/oxlint2/test/e2e.test.ts b/napi/oxlint2/test/e2e.test.ts
index 2c8e4287e6c8d..ed5e33d7c7b82 100644
--- a/napi/oxlint2/test/e2e.test.ts
+++ b/napi/oxlint2/test/e2e.test.ts
@@ -83,4 +83,13 @@ describe('oxlint2 CLI', () => {
     expect(exitCode).toBe(1);
     expect(normalizeOutput(stdout)).toMatchSnapshot();
   });
+
+  it('should report the correct severity when using a custom plugin', async () => {
+    const { stdout, exitCode } = await runOxlint(
+      'test/fixtures/basic_custom_plugin_warn_severity',
+    );
+
+    expect(exitCode).toBe(0);
+    expect(normalizeOutput(stdout)).toMatchSnapshot();
+  });
 });
diff --git a/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/.oxlintrc.json b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/.oxlintrc.json
new file mode 100644
index 0000000000000..0abdbdceb0e25
--- /dev/null
+++ b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/.oxlintrc.json
@@ -0,0 +1,7 @@
+{
+    "plugins": ["./test_plugin"],
+    "rules": {
+        "basic-custom-plugin/no-debugger": "warn"
+    },
+    "ignorePatterns": ["test_plugin"]
+}
diff --git a/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/index.js b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/index.js
new file mode 100644
index 0000000000000..eab74692130a6
--- /dev/null
+++ b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/index.js
@@ -0,0 +1 @@
+debugger;
diff --git a/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/test_plugin/index.js b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/test_plugin/index.js
new file mode 100644
index 0000000000000..d4e46f0bc4d7b
--- /dev/null
+++ b/napi/oxlint2/test/fixtures/basic_custom_plugin_warn_severity/test_plugin/index.js
@@ -0,0 +1,19 @@
+export default {
+  meta: {
+    name: "basic-custom-plugin",
+  },
+  rules: {
+    "no-debugger": {
+      create(context) {
+        return {
+          DebuggerStatement(debuggerStatement) {
+            context.report({
+              message: "Unexpected Debugger Statement",
+              node: debuggerStatement,
+            });
+          },
+        };
+      },
+    },
+  },
+};