diff --git a/src/core/components/parameter-row.jsx b/src/core/components/parameter-row.jsx
index fe171f6acca..a756a4ce30e 100644
--- a/src/core/components/parameter-row.jsx
+++ b/src/core/components/parameter-row.jsx
@@ -3,7 +3,7 @@ import { Map } from "immutable"
 import PropTypes from "prop-types"
 import ImPropTypes from "react-immutable-proptypes"
 import win from "core/window"
-import { getExtensions, getCommonExtensions } from "core/utils"
+import { getExtensions, getCommonExtensions, numberToString } from "core/utils"
 
 export default class ParameterRow extends Component {
   static propTypes = {
@@ -53,7 +53,7 @@ export default class ParameterRow extends Component {
     }
 
     if ( value !== undefined && value !== paramValue ) {
-      this.onChangeWrapper(value)
+      this.onChangeWrapper(numberToString(value))
     }
 
     this.setDefaultValue()
@@ -88,7 +88,7 @@ export default class ParameterRow extends Component {
           || paramWithMeta.getIn(["schema", "default"])
       }
       if(newValue !== undefined) {
-        this.onChangeWrapper(newValue)
+        this.onChangeWrapper(numberToString(newValue))
       }
     }
   }
diff --git a/src/core/utils.js b/src/core/utils.js
index 248ef59406a..3323a87dda5 100644
--- a/src/core/utils.js
+++ b/src/core/utils.js
@@ -780,4 +780,12 @@ export function stringify(thing) {
   }
 
   return thing.toString()
+}
+
+export function numberToString(thing) {
+  if(typeof thing === "number") {
+    return thing.toString()
+  }
+
+  return thing
 }
\ No newline at end of file
diff --git a/test/e2e/scenarios/bugs/4756.js b/test/e2e/scenarios/bugs/4756.js
new file mode 100644
index 00000000000..fca8e870326
--- /dev/null
+++ b/test/e2e/scenarios/bugs/4756.js
@@ -0,0 +1,43 @@
+describe("bug #4756: enum initial values", function () {
+  let mainPage
+  beforeEach(function (client, done) {
+    mainPage = client
+      .url("localhost:3230")
+      .page.main()
+
+    client.waitForElementVisible(".download-url-input:not([disabled])", 5000)
+      .pause(2000)
+      .clearValue(".download-url-input")
+      .setValue(".download-url-input", "http://localhost:3230/test-specs/bugs/4756.yaml")
+      .click("button.download-url-button")
+      .pause(1000)
+
+    done()
+  })
+
+  afterEach(function (client, done) {
+    done()
+  })
+
+  it("sets a required initial value based the first enum value", function (client) {
+    client.waitForElementVisible(".opblock-tag-section", 10000)
+      .click("#operations-default-post_zero")
+      .waitForElementVisible(".opblock.is-open", 5000)
+      .click("button.btn.try-out__btn")
+      .click("button.btn.execute")
+      .waitForElementVisible(".request-url", 2000)
+      .assert.containsText(".request-url > pre", "http://www.example.com/test/API/zero?one=0")
+    client.end()
+  })
+
+  it("sets a required initial value based on a default value", function (client) {
+    client.waitForElementVisible(".opblock-tag-section", 10000)
+      .click("#operations-default-post_one")
+      .waitForElementVisible(".opblock.is-open", 5000)
+      .click("button.btn.try-out__btn")
+      .click("button.btn.execute")
+      .waitForElementVisible(".request-url", 2000)
+      .assert.containsText(".request-url > pre", "http://www.example.com/test/API/one?one=1")
+    client.end()
+  })
+})
diff --git a/test/e2e/specs/bugs/4756.yaml b/test/e2e/specs/bugs/4756.yaml
new file mode 100644
index 00000000000..b1c142ea7b5
--- /dev/null
+++ b/test/e2e/specs/bugs/4756.yaml
@@ -0,0 +1,51 @@
+swagger: '2.0'
+info:
+  title: test doc
+  description: 'test doc '
+  license:
+    name: Copyright @2018
+  version: 1.0.0
+host: www.example.com
+basePath: /test/API
+tags:
+  - name: devices
+    description: devices
+schemes:
+  - http
+  - https
+consumes:
+  - application/x-www-form-urlencoded
+produces:
+  - application/json
+paths:
+  /zero:
+    post:
+      parameters:
+        - in: query
+          name: one
+          type: string
+          required: true
+          enum: 
+            - 0
+            - 1
+      responses:
+        200:
+          description: 'response'
+          examples: 
+            application/json: {"error":0}
+  /one:
+    post:
+      parameters:
+        - in: query
+          name: one
+          type: string
+          required: true
+          default: 1
+          enum: 
+            - 0
+            - 1
+      responses:
+        200:
+          description: 'response'
+          examples: 
+            application/json: {"error":0}
\ No newline at end of file