diff --git a/options/locale/locale_en-US.ini b/options/locale/locale_en-US.ini
index 69923ebb83..40e4e0c0ba 100644
--- a/options/locale/locale_en-US.ini
+++ b/options/locale/locale_en-US.ini
@@ -1887,6 +1887,7 @@ diff.file_image_width = Width
 diff.file_image_height = Height
 diff.file_byte_size = Size
 diff.file_suppressed = File diff suppressed because it is too large
+diff.file_suppressed_line_too_long = File diff suppressed because one or more lines are too long
 diff.too_many_files = Some files were not shown because too many files changed in this diff
 diff.comment.placeholder = Leave a comment
 diff.comment.markdown_info = Styling with markdown is supported.
diff --git a/services/gitdiff/gitdiff.go b/services/gitdiff/gitdiff.go
index 2ca6bd957e..f8f0fd7e3b 100644
--- a/services/gitdiff/gitdiff.go
+++ b/services/gitdiff/gitdiff.go
@@ -574,21 +574,22 @@ func (diffSection *DiffSection) GetComputedInlineDiffFor(diffLine *DiffLine) tem
 
 // DiffFile represents a file diff.
 type DiffFile struct {
-	Name               string
-	OldName            string
-	Index              int
-	Addition, Deletion int
-	Type               DiffFileType
-	IsCreated          bool
-	IsDeleted          bool
-	IsBin              bool
-	IsLFSFile          bool
-	IsRenamed          bool
-	IsAmbiguous        bool
-	IsSubmodule        bool
-	Sections           []*DiffSection
-	IsIncomplete       bool
-	IsProtected        bool
+	Name                    string
+	OldName                 string
+	Index                   int
+	Addition, Deletion      int
+	Type                    DiffFileType
+	IsCreated               bool
+	IsDeleted               bool
+	IsBin                   bool
+	IsLFSFile               bool
+	IsRenamed               bool
+	IsAmbiguous             bool
+	IsSubmodule             bool
+	Sections                []*DiffSection
+	IsIncomplete            bool
+	IsIncompleteLineTooLong bool
+	IsProtected             bool
 }
 
 // GetType returns type of diff file.
@@ -935,6 +936,7 @@ func parseHunks(curFile *DiffFile, maxLines, maxLineCharacters int, input *bufio
 	for {
 		for isFragment {
 			curFile.IsIncomplete = true
+			curFile.IsIncompleteLineTooLong = true
 			_, isFragment, err = input.ReadLine()
 			if err != nil {
 				// Now by the definition of ReadLine this cannot be io.EOF
@@ -1062,6 +1064,7 @@ func parseHunks(curFile *DiffFile, maxLines, maxLineCharacters int, input *bufio
 		line := string(lineBytes)
 		if isFragment {
 			curFile.IsIncomplete = true
+			curFile.IsIncompleteLineTooLong = true
 			for isFragment {
 				lineBytes, isFragment, err = input.ReadLine()
 				if err != nil {
@@ -1073,6 +1076,7 @@ func parseHunks(curFile *DiffFile, maxLines, maxLineCharacters int, input *bufio
 		}
 		if len(line) > maxLineCharacters {
 			curFile.IsIncomplete = true
+			curFile.IsIncompleteLineTooLong = true
 			line = line[:maxLineCharacters]
 		}
 		curSection.Lines[len(curSection.Lines)-1].Content = line
diff --git a/templates/repo/diff/box.tmpl b/templates/repo/diff/box.tmpl
index 4408d52575..9a2f7bdd7f 100644
--- a/templates/repo/diff/box.tmpl
+++ b/templates/repo/diff/box.tmpl
@@ -53,7 +53,13 @@
 						</div>
 						<span class="file mono">{{$file.Name}}</span>
 						<div class="diff-file-header-actions df ac">
-							<div class="text grey">{{$.i18n.Tr "repo.diff.file_suppressed"}}</div>
+							<div class="text grey">
+								{{if $file.IsIncompleteLineTooLong}}
+									{{$.i18n.Tr "repo.diff.file_suppressed_line_too_long"}}
+								{{else}}
+									{{$.i18n.Tr "repo.diff.file_suppressed"}}
+								{{end}}
+							</div>
 							{{if $file.IsProtected}}
 								<span class="ui basic label">{{$.i18n.Tr "repo.diff.protected"}}</span>
 							{{end}}