diff --git a/src/Microsoft.AspNetCore.Routing/RouteCollection.cs b/src/Microsoft.AspNetCore.Routing/RouteCollection.cs
index 0d93c1f9ac..1d359cee57 100644
--- a/src/Microsoft.AspNetCore.Routing/RouteCollection.cs
+++ b/src/Microsoft.AspNetCore.Routing/RouteCollection.cs
@@ -139,7 +139,7 @@ namespace Microsoft.AspNetCore.Routing
 
             var url = pathData.VirtualPath;
 
-            if (!string.IsNullOrEmpty(url) && (_options.LowercaseUrls || _options.AppendTrailingSlash))
+            if (!string.IsNullOrEmpty(url) && (_options.LowercaseUrls || _options.LowercaseQueryStrings || _options.AppendTrailingSlash))
             {
                 var indexOfSeparator = url.IndexOfAny(UrlQueryDelimiters);
                 var urlWithoutQueryString = url;
@@ -154,11 +154,11 @@ namespace Microsoft.AspNetCore.Routing
                 if (_options.LowercaseUrls)
                 {
                     urlWithoutQueryString = urlWithoutQueryString.ToLowerInvariant();
+                }
 
-                    if (!string.IsNullOrEmpty(queryString))
-                    {
-                        queryString = queryString.ToLowerInvariant();
-                    }
+                if (_options.LowercaseQueryStrings)
+                {
+                    queryString = queryString.ToLowerInvariant();
                 }
 
                 if (_options.AppendTrailingSlash && !urlWithoutQueryString.EndsWith("/"))
diff --git a/src/Microsoft.AspNetCore.Routing/RouteOptions.cs b/src/Microsoft.AspNetCore.Routing/RouteOptions.cs
index 1ae47ed13f..45f5589ed0 100644
--- a/src/Microsoft.AspNetCore.Routing/RouteOptions.cs
+++ b/src/Microsoft.AspNetCore.Routing/RouteOptions.cs
@@ -10,10 +10,15 @@ namespace Microsoft.AspNetCore.Routing
     public class RouteOptions
     {
         /// <summary>
-        /// Gets or sets a value indicating whether all generated URLs are lower-case.
+        /// Gets or sets a value indicating whether all generated URLs are lower-case. it doesn't include the query string.
         /// </summary>
         public bool LowercaseUrls { get; set; }
 
+        /// <summary>
+        /// Gets or sets a value indicating whether all generated QUERY STRINGS are lower-case.
+        /// </summary>
+        public bool LowercaseQueryStrings { get; set; }
+
         /// <summary>
         /// Gets or sets a value indicating whether a trailing slash should be appended to the generated URLs.
         /// </summary>