diff --git a/components/prism-csharp.js b/components/prism-csharp.js
index 50ee493ee1..e6f83d3cc1 100644
--- a/components/prism-csharp.js
+++ b/components/prism-csharp.js
@@ -4,6 +4,12 @@ Prism.languages.csharp = Prism.languages.extend('clike', {
 		/@("|')(\1\1|\\\1|\\?(?!\1)[\s\S])*\1/,
 		/("|')(\\?.)*?\1/
 	],
-	'preprocessor': /^\s*#.*/m,
 	'number': /\b-?(0x[\da-f]+|\d*\.?\d+)\b/i
 });
+
+Prism.languages.insertBefore('csharp', 'keyword', {
+	'preprocessor': {
+		pattern: /(^\s*)#.*/m,
+		lookbehind: true
+	}
+});
diff --git a/components/prism-csharp.min.js b/components/prism-csharp.min.js
index abde3d03c6..f9b3c9bd2f 100644
--- a/components/prism-csharp.min.js
+++ b/components/prism-csharp.min.js
@@ -1 +1 @@
-Prism.languages.csharp=Prism.languages.extend("clike",{keyword:/\b(abstract|as|async|await|base|bool|break|byte|case|catch|char|checked|class|const|continue|decimal|default|delegate|do|double|else|enum|event|explicit|extern|false|finally|fixed|float|for|foreach|goto|if|implicit|in|int|interface|internal|is|lock|long|namespace|new|null|object|operator|out|override|params|private|protected|public|readonly|ref|return|sbyte|sealed|short|sizeof|stackalloc|static|string|struct|switch|this|throw|true|try|typeof|uint|ulong|unchecked|unsafe|ushort|using|virtual|void|volatile|while|add|alias|ascending|async|await|descending|dynamic|from|get|global|group|into|join|let|orderby|partial|remove|select|set|value|var|where|yield)\b/,string:[/@("|')(\1\1|\\\1|\\?(?!\1)[\s\S])*\1/,/("|')(\\?.)*?\1/],preprocessor:/^\s*#.*/m,number:/\b-?(0x[\da-f]+|\d*\.?\d+)\b/i});
\ No newline at end of file
+Prism.languages.csharp=Prism.languages.extend("clike",{keyword:/\b(abstract|as|async|await|base|bool|break|byte|case|catch|char|checked|class|const|continue|decimal|default|delegate|do|double|else|enum|event|explicit|extern|false|finally|fixed|float|for|foreach|goto|if|implicit|in|int|interface|internal|is|lock|long|namespace|new|null|object|operator|out|override|params|private|protected|public|readonly|ref|return|sbyte|sealed|short|sizeof|stackalloc|static|string|struct|switch|this|throw|true|try|typeof|uint|ulong|unchecked|unsafe|ushort|using|virtual|void|volatile|while|add|alias|ascending|async|await|descending|dynamic|from|get|global|group|into|join|let|orderby|partial|remove|select|set|value|var|where|yield)\b/,string:[/@("|')(\1\1|\\\1|\\?(?!\1)[\s\S])*\1/,/("|')(\\?.)*?\1/],number:/\b-?(0x[\da-f]+|\d*\.?\d+)\b/i}),Prism.languages.insertBefore("csharp","keyword",{preprocessor:{pattern:/(^\s*)#.*/m,lookbehind:!0}});
\ No newline at end of file