diff --git a/src/execute/oas3/build-request.js b/src/execute/oas3/build-request.js
index 0b928c415..a2182c285 100644
--- a/src/execute/oas3/build-request.js
+++ b/src/execute/oas3/build-request.js
@@ -55,36 +55,9 @@ export default function (options, req) {
             req.form = {}
             Object.keys(requestBody).forEach((k) => {
               const val = requestBody[k]
-              let newVal
-
-              let isFile
-
-              if (typeof File !== 'undefined') {
-                isFile = val instanceof File // eslint-disable-line no-undef
-              }
-
-              if (typeof Blob !== 'undefined') {
-                isFile = isFile || val instanceof Blob // eslint-disable-line no-undef
-              }
-
-              if (typeof Buffer !== 'undefined') {
-                isFile = isFile || Buffer.isBuffer(val)
-              }
-
-              if (typeof val === 'object' && !isFile) {
-                if (Array.isArray(val)) {
-                  newVal = val.toString()
-                }
-                else {
-                  newVal = JSON.stringify(val)
-                }
-              }
-              else {
-                newVal = val
-              }
 
               req.form[k] = {
-                value: newVal
+                value: toPartContent(val, true)
               }
             })
           }
@@ -105,6 +78,34 @@ export default function (options, req) {
   return req
 }
 
+function toPartContent(val, inspectArrays){
+  if (inspectArrays && Array.isArray(val)) {
+    // setting 'inspectArrays' to false to avoid cycles in arrays that contain themselves
+    return val.map(v => toPartContent(v, false))
+  }
+
+  let isFile
+
+  if (typeof File !== 'undefined') {
+    isFile = val instanceof File // eslint-disable-line no-undef
+  }
+
+  if (typeof Blob !== 'undefined') {
+    isFile = isFile || val instanceof Blob // eslint-disable-line no-undef
+  }
+
+  if (typeof Buffer !== 'undefined') {
+    isFile = isFile || Buffer.isBuffer(val)
+  }
+
+  if (typeof val === 'object' && !isFile) {
+      return JSON.stringify(val)
+  }
+  else {
+    return val
+  }
+}
+
 // Add security values, to operations - that declare their need on them
 // Adapted from the Swagger2 implementation
 export function applySecurities({request, securities = {}, operation = {}, spec}) {
diff --git a/src/http.js b/src/http.js
index 934baecd7..1d1313481 100644
--- a/src/http.js
+++ b/src/http.js
@@ -254,7 +254,12 @@ export function mergeInQueryOrForm(req = {}) {
       const FormData = require('isomorphic-form-data') // eslint-disable-line global-require
       req.body = new FormData()
       Object.keys(form).forEach((key) => {
-        req.body.append(key, formatValue(form[key], true))
+        const val = form[key]
+        if (Array.isArray(val.value)){
+          val.value.forEach(v => req.body.append(key, formatValue({value: v}, true)))
+        } else {
+          req.body.append(key, formatValue(val, true))
+        }
       })
     }
     else {