diff --git a/_test/extra.txt b/_test/extra.txt
index 41b1d7d..8c9578f 100644
--- a/_test/extra.txt
+++ b/_test/extra.txt
@@ -380,3 +380,10 @@ a* b c d *e*
 //- - - - - - - - -//
 <aaa >
 //= = = = = = = = = = = = = = = = = = = = = = = =//
+
+25: code block starts with tab
+//- - - - - - - - -//
+		x
+//- - - - - - - - -//
+<pre><code>	x</code></pre>
+//= = = = = = = = = = = = = = = = = = = = = = = =//
diff --git a/parser/code_block.go b/parser/code_block.go
index c16ea41..732f18c 100644
--- a/parser/code_block.go
+++ b/parser/code_block.go
@@ -31,6 +31,10 @@ func (b *codeBlockParser) Open(parent ast.Node, reader text.Reader, pc Context)
 	node := ast.NewCodeBlock()
 	reader.AdvanceAndSetPadding(pos, padding)
 	_, segment = reader.PeekLine()
+	// if code block line starts with a tab, keep a tab as it is.
+	if segment.Padding != 0 {
+		preserveLeadingTabInCodeBlock(&segment, reader, 0)
+	}
 	node.Lines().Append(segment)
 	reader.Advance(segment.Len() - 1)
 	return node, NoChildren