diff --git a/TypeScript.YAML-tmLanguage b/TypeScript.YAML-tmLanguage
index 36fa5547..f04e137e 100644
--- a/TypeScript.YAML-tmLanguage
+++ b/TypeScript.YAML-tmLanguage
@@ -2927,7 +2927,7 @@ repository:
 
   directives:
     name: comment.line.triple-slash.directive.ts
-    begin: ^(///)\s*(?=<(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode)\s*=\s*({{quotedStrings}}))+\s*/>\s*$)
+    begin: ^(///)\s*(?=<(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode|preserve)\s*=\s*({{quotedStrings}}))+\s*/>\s*$)
     beginCaptures:
       '1': { name: punctuation.definition.comment.ts }
     end: (?=$)
@@ -2942,7 +2942,7 @@ repository:
         '0': { name: punctuation.definition.tag.directive.ts }
       patterns:
       - name: entity.other.attribute-name.directive.ts
-        match: 'path|types|no-default-lib|lib|name|resolution-mode'
+        match: 'path|types|no-default-lib|lib|name|resolution-mode|preserve'
       - name: keyword.operator.assignment.ts
         match: '='
       - include: '#string'
diff --git a/TypeScript.tmLanguage b/TypeScript.tmLanguage
index 4d91f6ad..d89ecc08 100644
--- a/TypeScript.tmLanguage
+++ b/TypeScript.tmLanguage
@@ -8951,7 +8951,7 @@
         <key>name</key>
         <string>comment.line.triple-slash.directive.ts</string>
         <key>begin</key>
-        <string>^(///)\s*(?=&lt;(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode)\s*=\s*((\'([^\'\\]|\\.)*\')|(\"([^\"\\]|\\.)*\")|(\`([^\`\\]|\\.)*\`)))+\s*/&gt;\s*$)</string>
+        <string>^(///)\s*(?=&lt;(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode|preserve)\s*=\s*((\'([^\'\\]|\\.)*\')|(\"([^\"\\]|\\.)*\")|(\`([^\`\\]|\\.)*\`)))+\s*/&gt;\s*$)</string>
         <key>beginCaptures</key>
         <dict>
           <key>1</key>
@@ -8998,7 +8998,7 @@
                 <key>name</key>
                 <string>entity.other.attribute-name.directive.ts</string>
                 <key>match</key>
-                <string>path|types|no-default-lib|lib|name|resolution-mode</string>
+                <string>path|types|no-default-lib|lib|name|resolution-mode|preserve</string>
               </dict>
               <dict>
                 <key>name</key>
diff --git a/TypeScriptReact.tmLanguage b/TypeScriptReact.tmLanguage
index a7aec5da..ff57281f 100644
--- a/TypeScriptReact.tmLanguage
+++ b/TypeScriptReact.tmLanguage
@@ -8899,7 +8899,7 @@
         <key>name</key>
         <string>comment.line.triple-slash.directive.tsx</string>
         <key>begin</key>
-        <string>^(///)\s*(?=&lt;(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode)\s*=\s*((\'([^\'\\]|\\.)*\')|(\"([^\"\\]|\\.)*\")|(\`([^\`\\]|\\.)*\`)))+\s*/&gt;\s*$)</string>
+        <string>^(///)\s*(?=&lt;(reference|amd-dependency|amd-module)(\s+(path|types|no-default-lib|lib|name|resolution-mode|preserve)\s*=\s*((\'([^\'\\]|\\.)*\')|(\"([^\"\\]|\\.)*\")|(\`([^\`\\]|\\.)*\`)))+\s*/&gt;\s*$)</string>
         <key>beginCaptures</key>
         <dict>
           <key>1</key>
@@ -8946,7 +8946,7 @@
                 <key>name</key>
                 <string>entity.other.attribute-name.directive.tsx</string>
                 <key>match</key>
-                <string>path|types|no-default-lib|lib|name|resolution-mode</string>
+                <string>path|types|no-default-lib|lib|name|resolution-mode|preserve</string>
               </dict>
               <dict>
                 <key>name</key>
diff --git a/tests/baselines/Issue1066.baseline.txt b/tests/baselines/Issue1066.baseline.txt
new file mode 100644
index 00000000..a99fae61
--- /dev/null
+++ b/tests/baselines/Issue1066.baseline.txt
@@ -0,0 +1,44 @@
+original file
+-----------------------------------
+/// <reference path="../communication-api.d.ts" preserve="true" />
+-----------------------------------
+
+Grammar: TypeScript.tmLanguage
+-----------------------------------
+>/// <reference path="../communication-api.d.ts" preserve="true" />
+ ^^^
+ source.ts comment.line.triple-slash.directive.ts punctuation.definition.comment.ts
+    ^
+    source.ts comment.line.triple-slash.directive.ts
+     ^
+     source.ts comment.line.triple-slash.directive.ts meta.tag.ts punctuation.definition.tag.directive.ts
+      ^^^^^^^^^
+      source.ts comment.line.triple-slash.directive.ts meta.tag.ts entity.name.tag.directive.ts
+               ^
+               source.ts comment.line.triple-slash.directive.ts meta.tag.ts
+                ^^^^
+                source.ts comment.line.triple-slash.directive.ts meta.tag.ts entity.other.attribute-name.directive.ts
+                    ^
+                    source.ts comment.line.triple-slash.directive.ts meta.tag.ts keyword.operator.assignment.ts
+                     ^
+                     source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts punctuation.definition.string.begin.ts
+                      ^^^^^^^^^^^^^^^^^^^^^^^^^
+                      source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts
+                                               ^
+                                               source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts punctuation.definition.string.end.ts
+                                                ^
+                                                source.ts comment.line.triple-slash.directive.ts meta.tag.ts
+                                                 ^^^^^^^^
+                                                 source.ts comment.line.triple-slash.directive.ts meta.tag.ts entity.other.attribute-name.directive.ts
+                                                         ^
+                                                         source.ts comment.line.triple-slash.directive.ts meta.tag.ts keyword.operator.assignment.ts
+                                                          ^
+                                                          source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts punctuation.definition.string.begin.ts
+                                                           ^^^^
+                                                           source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts
+                                                               ^
+                                                               source.ts comment.line.triple-slash.directive.ts meta.tag.ts string.quoted.double.ts punctuation.definition.string.end.ts
+                                                                ^
+                                                                source.ts comment.line.triple-slash.directive.ts meta.tag.ts
+                                                                 ^^
+                                                                 source.ts comment.line.triple-slash.directive.ts meta.tag.ts punctuation.definition.tag.directive.ts
\ No newline at end of file
diff --git a/tests/cases/Issue1066.ts b/tests/cases/Issue1066.ts
new file mode 100644
index 00000000..660bed57
--- /dev/null
+++ b/tests/cases/Issue1066.ts
@@ -0,0 +1 @@
+/// <reference path="../communication-api.d.ts" preserve="true" />
\ No newline at end of file