diff --git a/AFNetworking/AFHTTPClient.m b/AFNetworking/AFHTTPClient.m
index b859313..a157dbe 100644
--- a/AFNetworking/AFHTTPClient.m
+++ b/AFNetworking/AFHTTPClient.m
@@ -80,11 +80,16 @@ static NSString * AFBase64EncodedStringFromString(NSString *string) {
     return [[NSString alloc] initWithData:mutableData encoding:NSASCIIStringEncoding];
 }
 
-static NSString * AFPercentEscapedQueryStringPairMemberFromStringWithEncoding(NSString *string, NSStringEncoding encoding) {
-    static NSString * const kAFCharactersToBeEscaped = @":/?&=;+!@#$()',*";
-    static NSString * const kAFCharactersToLeaveUnescaped = @"[].";
+static NSString * const kAFCharactersToBeEscapedInQueryString = @":/?&=;+!@#$()',*";
 
-	return (__bridge_transfer  NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (__bridge CFStringRef)string, (__bridge CFStringRef)kAFCharactersToLeaveUnescaped, (__bridge CFStringRef)kAFCharactersToBeEscaped, CFStringConvertNSStringEncodingToEncoding(encoding));
+static NSString * AFPercentEscapedQueryStringPairKeyFromStringWithEncoding(NSString *string, NSStringEncoding encoding) {
+    static NSString * const kAFCharactersToLeaveUnescapedInQueryStringPairKey = @"[].";
+
+	return (__bridge_transfer  NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (__bridge CFStringRef)string, (__bridge CFStringRef)kAFCharactersToLeaveUnescapedInQueryStringPairKey, (__bridge CFStringRef)kAFCharactersToBeEscapedInQueryString, CFStringConvertNSStringEncodingToEncoding(encoding));
+}
+
+static NSString * AFPercentEscapedQueryStringPairValueFromStringWithEncoding(NSString *string, NSStringEncoding encoding) {
+	return (__bridge_transfer  NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (__bridge CFStringRef)string, NULL, (__bridge CFStringRef)kAFCharactersToBeEscapedInQueryString, CFStringConvertNSStringEncodingToEncoding(encoding));
 }
 
 #pragma mark -
@@ -116,9 +121,9 @@ static NSString * AFPercentEscapedQueryStringPairMemberFromStringWithEncoding(NS
 
 - (NSString *)URLEncodedStringValueWithEncoding:(NSStringEncoding)stringEncoding {
     if (!self.value || [self.value isEqual:[NSNull null]]) {
-        return AFPercentEscapedQueryStringPairMemberFromStringWithEncoding([self.field description], stringEncoding);
+        return AFPercentEscapedQueryStringPairValueFromStringWithEncoding([self.field description], stringEncoding);
     } else {
-        return [NSString stringWithFormat:@"%@=%@", AFPercentEscapedQueryStringPairMemberFromStringWithEncoding([self.field description], stringEncoding), AFPercentEscapedQueryStringPairMemberFromStringWithEncoding([self.value description], stringEncoding)];
+        return [NSString stringWithFormat:@"%@=%@", AFPercentEscapedQueryStringPairValueFromStringWithEncoding([self.field description], stringEncoding), AFPercentEscapedQueryStringPairKeyFromStringWithEncoding([self.value description], stringEncoding)];
     }
 }