diff --git a/main.go b/main.go
index d861ee6..fd26489 100644
--- a/main.go
+++ b/main.go
@@ -25,7 +25,6 @@ var (
 	recurse      bool
 	sortOutput   bool
 	silent       bool
-	printTree    bool // for debugging
 )
 
 // Initialize flags.
@@ -35,7 +34,6 @@ func init() {
 	flag.BoolVar(&recurse, "R", false, "recurse into directories in the file list")
 	flag.BoolVar(&sortOutput, "sort", true, "sort tags")
 	flag.BoolVar(&silent, "silent", false, "do not produce any output on error")
-	flag.BoolVar(&printTree, "tree", false, "print syntax tree (debugging)")
 
 	flag.Usage = func() {
 		fmt.Fprintf(os.Stderr, "gotags version %s\n\n", Version)
@@ -142,11 +140,6 @@ func main() {
 		os.Exit(1)
 	}
 
-	if printTree {
-		PrintTree(flag.Arg(0))
-		return
-	}
-
 	tags := []Tag{}
 	for _, file := range files {
 		ts, err := Parse(file)
diff --git a/parser.go b/parser.go
index eb92fb6..e9c2686 100644
--- a/parser.go
+++ b/parser.go
@@ -15,18 +15,6 @@ type tagParser struct {
 	types []string // all types we encounter, used to determine the constructors
 }
 
-// PrintTree prints the ast of the source in filename.
-func PrintTree(filename string) error {
-	fset := token.NewFileSet()
-	f, err := parser.ParseFile(fset, filename, nil, 0)
-	if err != nil {
-		return err
-	}
-
-	ast.Print(fset, f)
-	return nil
-}
-
 // Parse parses the source in filename and returns a list of tags.
 func Parse(filename string) ([]Tag, error) {
 	p := &tagParser{