diff --git a/src/index.js b/src/index.js
index 6d09bb9..438d577 100644
--- a/src/index.js
+++ b/src/index.js
@@ -28,6 +28,9 @@ function isRegExp(string) {
 // So we need to offer a way to customize the cwd for the eslint plugin
 export function manipulatePluginOptions(pluginOpts, cwd = process.cwd()) {
   if (pluginOpts.root) {
+    if (typeof pluginOpts.root === 'string') {
+      pluginOpts.root = [pluginOpts.root]; // eslint-disable-line no-param-reassign
+    }
     // eslint-disable-next-line no-param-reassign
     pluginOpts.root = pluginOpts.root.reduce((resolvedDirs, dirPath) => {
       if (glob.hasMagic(dirPath)) {
diff --git a/test/index.test.js b/test/index.test.js
index 892979b..26df920 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -109,13 +109,18 @@ describe('module-resolver', () => {
         babelrc: false,
         plugins: [
           [plugin, {
-            root: [
-              './test/testproject/src',
-            ],
+            root: './test/testproject/src',
           }],
         ],
       };
 
+      it('should convert root to array if root is a string', () => {
+        const code = 'var something = require();';
+        const result = transform(code, rootTransformerOpts);
+
+        expect(result.code).toBe('var something = require();');
+      });
+
       it('should handle no arguments', () => {
         const code = 'var something = require();';
         const result = transform(code, rootTransformerOpts);
@@ -213,9 +218,7 @@ describe('module-resolver', () => {
         babelrc: false,
         plugins: [
           [plugin, {
-            root: [
-              './test/testproject/src/**',
-            ],
+            root: './test/testproject/src/**',
           }],
         ],
       };
@@ -464,9 +467,7 @@ describe('module-resolver', () => {
         babelrc: false,
         plugins: [
           [plugin, {
-            root: [
-              './testproject/src',
-            ],
+            root: './testproject/src',
             alias: {
               test: './testproject/test',
             },
@@ -498,9 +499,7 @@ describe('module-resolver', () => {
       babelrc: false,
       plugins: [
         [plugin, {
-          root: [
-            './src',
-          ],
+          root: './src',
           alias: {
             test: './test',
           },
@@ -531,9 +530,7 @@ describe('module-resolver', () => {
         babelrc: false,
         plugins: [
           [plugin, {
-            root: [
-              './src',
-            ],
+            root: './src',
             cwd: 'babelrc',
           }],
         ],
@@ -571,9 +568,7 @@ describe('module-resolver', () => {
         babelrc: false,
         plugins: [
           [pluginWithMock, {
-            root: [
-              '.',
-            ],
+            root: '.',
             cwd: 'babelrc',
           }],
         ],
diff --git a/test/jest.test.js b/test/jest.test.js
index 0261004..82c7f2e 100644
--- a/test/jest.test.js
+++ b/test/jest.test.js
@@ -7,9 +7,7 @@ describe('jest functions', () => {
     babelrc: false,
     plugins: [
       [plugin, {
-        root: [
-          './test/testproject/src',
-        ],
+        root: './test/testproject/src',
         alias: {
           test: './test/testproject/test',
         },
diff --git a/test/system.test.js b/test/system.test.js
index 74b0e44..bd4c254 100644
--- a/test/system.test.js
+++ b/test/system.test.js
@@ -7,9 +7,7 @@ describe('System.import', () => {
     babelrc: false,
     plugins: [
       [plugin, {
-        root: [
-          './test/testproject/src',
-        ],
+        root: './test/testproject/src',
         alias: {
           test: './test/testproject/test',
         },