diff --git a/models/issue.go b/models/issue.go
index de3243cd58..04b9b3551f 100644
--- a/models/issue.go
+++ b/models/issue.go
@@ -74,8 +74,8 @@ var (
 	issueTasksDonePat *regexp.Regexp
 )
 
-const issueTasksRegexpStr = `(^\s*[-*]\s\[[\sx]\]\s.)|(\n\s*[-*]\s\[[\sx]\]\s.)`
-const issueTasksDoneRegexpStr = `(^\s*[-*]\s\[[x]\]\s.)|(\n\s*[-*]\s\[[x]\]\s.)`
+const issueTasksRegexpStr = `(^\s*[-*]\s\[[\sxX]\]\s.)|(\n\s*[-*]\s\[[\sxX]\]\s.)`
+const issueTasksDoneRegexpStr = `(^\s*[-*]\s\[[xX]\]\s.)|(\n\s*[-*]\s\[[xX]\]\s.)`
 const issueMaxDupIndexAttempts = 3
 
 func init() {