diff --git a/src/main/scala/gitbucket/core/controller/ApiController.scala b/src/main/scala/gitbucket/core/controller/ApiController.scala
index 784d025..fda5fdc 100644
--- a/src/main/scala/gitbucket/core/controller/ApiController.scala
+++ b/src/main/scala/gitbucket/core/controller/ApiController.scala
@@ -811,7 +811,7 @@
           ApiCommits(
             repositoryName = RepositoryName(repository),
             commitInfo = commitInfo,
-            diffs = JGitUtil.getDiffs(git, Some(commitInfo.parents.head), commitInfo.id, false, true),
+            diffs = JGitUtil.getDiffs(git, commitInfo.parents.headOption, commitInfo.id, false, true),
             author = getAccount(commitInfo.authorName, commitInfo.authorEmailAddress),
             committer = getAccount(commitInfo.committerName, commitInfo.committerEmailAddress),
             commentCount = getCommitComment(repository.owner, repository.name, sha).size