diff --git a/src/pure/runner.ts b/src/pure/runner.ts
index a21e75e5..a8ab20f4 100644
--- a/src/pure/runner.ts
+++ b/src/pure/runner.ts
@@ -6,6 +6,7 @@ import {
   filterColorFormatOutput,
   sanitizeFilePath,
 } from './utils'
+import { isWindows } from './platform'
 import type { StartConfig } from './ApiProcess'
 import { runVitestWithApi } from './ApiProcess'
 
@@ -77,8 +78,15 @@ export class TestRunner {
     if (updateSnapshot)
       args.push('--update')
 
-    if (testNamePattern)
-      args.push('-t', testNamePattern.replace(/[$^+?()[\]]/g, '\\$&'))
+    if (testNamePattern) {
+      // Vitest's test name pattern is a regex, so we need to escape any special regex characters.
+      // Additionally, when a custom start process is not used on Windows, child_process.spawn is used with shell: true.
+      // That disables automatic quoting/escaping of arguments, requiring us to manually perform that here as well.
+      if (isWindows && !customStartProcess)
+        args.push('-t', `"${testNamePattern.replace(/[$^+?()[\]"]/g, '\\$&')}"`)
+      else
+        args.push('-t', testNamePattern.replace(/[$^+?()[\]"]/g, '\\$&'))
+    }
 
     const workspacePath = sanitizeFilePath(this.workspacePath, false)
     const outputs: string[] = []
diff --git a/test/runner.test.ts b/test/runner.test.ts
new file mode 100644
index 00000000..c347a5f5
--- /dev/null
+++ b/test/runner.test.ts
@@ -0,0 +1,82 @@
+import { afterEach, describe, expect, test, vi } from 'vitest'
+import { TestRunner } from '../src/pure/runner'
+import * as platformConstants from '../src/pure/platform'
+
+// Mock vscode ("pure" modules aren't quite pure)
+vi.mock('vscode', () => {
+  return {
+    default: { myDefaultKey: vi.fn() },
+    namedExport: vi.fn(),
+    window: {
+      createOutputChannel: () => {
+        return {
+          appendLine: vi.fn(),
+        }
+      },
+    },
+  }
+})
+
+// Mock config
+vi.mock('../src/config', () => {
+  return {
+    getConfig: () => {
+      return {
+        env: null,
+      }
+    },
+  }
+})
+
+// Mock runVitestWithApi, causing it to return its arguments as its output to allow us to assert their values
+vi.mock('../src/pure/ApiProcess', () => {
+  return {
+    runVitestWithApi: (
+      vitest: { cmd: string; args: string[] },
+      workspace: string,
+      handlers: any,
+      customStartProcess?: (config: any) => void,
+    ) => {
+      return `vitest.cmd=${vitest.cmd}`
+        + ` vitest.args=${vitest.args}`
+        + ` workspace=${workspace}`
+        + ` customStartProcess=${!!customStartProcess}`
+    },
+  }
+})
+
+describe('TestRunner', () => {
+  const prevIsWindows = platformConstants.isWindows
+
+  afterEach(() => {
+    Object.defineProperty(platformConstants, 'isWindows', { value: prevIsWindows, writable: true })
+  })
+
+  test.each([
+    [false, false, 'vitest,abc.spec.ts,-t,a \\(b\\) \\\"c\\\" d'],
+    [false, true, 'vitest,abc.spec.ts,-t,a \\(b\\) \\\"c\\\" d'],
+    [true, false, 'vitest,abc.spec.ts,-t,\"a \\(b\\) \\\"c\\\" d\"'],
+    [true, true, 'vitest,abc.spec.ts,-t,a \\(b\\) \\\"c\\\" d'],
+  ])('scheduleRun properly escapes arguments (isWindows: %s, customStartProcess: %s)', async (isWindows, useCustomStartProcess, expectedArgs) => {
+    Object.defineProperty(platformConstants, 'isWindows', { value: isWindows, writable: true })
+
+    const workspacePath = '/test'
+    const testFiles = ['abc.spec.ts']
+    const testNamePattern = 'a (b) "c" d'
+    const customStartProcess = useCustomStartProcess ? () => {} : undefined
+
+    const { testResultFiles, output } = await new TestRunner(workspacePath, undefined).scheduleRun(
+      testFiles,
+      testNamePattern,
+      undefined,
+      undefined,
+      undefined,
+      undefined,
+      undefined,
+      customStartProcess,
+    )
+
+    expect(testResultFiles).toBeDefined()
+    expect(output).toBe(`vitest.cmd=npx vitest.args=${expectedArgs} workspace=/test customStartProcess=${useCustomStartProcess}`)
+  })
+})