diff --git a/cmd/goast/cli.go b/cmd/goast/cli.go
index 9919a9f..54dc402 100644
--- a/cmd/goast/cli.go
+++ b/cmd/goast/cli.go
@@ -271,8 +271,11 @@ func cmdEval() *cli.Command {
 			switch f {
 			case outputText:
 				for _, fail := range failCases {
-					fmt.Fprintf(w, "[%s:%d] - %s\n", fail.Path, fail.Line, fail.Msg)
+					if err := outputFailAsText(w, fail); err != nil {
+						return err
+					}
 				}
+
 				fmt.Fprintf(w, "\n\tDetected %d violations\n\n", len(failCases))
 
 			case outputJSON:
diff --git a/cmd/goast/output.go b/cmd/goast/output.go
new file mode 100644
index 0000000..16e7fb0
--- /dev/null
+++ b/cmd/goast/output.go
@@ -0,0 +1,70 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"unicode"
+
+	"github.com/fatih/color"
+	"github.com/m-mizutani/goast"
+	"github.com/m-mizutani/goerr"
+)
+
+func outputFailAsText(w io.Writer, fail *goast.Fail) error {
+	code, err := getLine(fail.Path, fail.Line)
+	if err != nil {
+		return err
+	}
+
+	type fprintf func(w io.Writer, format string, a ...any) (n int, err error)
+
+	underLine := make([]rune, len(code))
+	for i, c := range code {
+		if i+1 < fail.Column {
+			switch {
+			case unicode.IsSpace(c):
+				underLine[i] = c
+			case i+1 < fail.Column:
+				underLine[i] = ' '
+			}
+		} else {
+			underLine[i] = '~'
+		}
+	}
+
+	var cFprintf fprintf = fmt.Fprintf
+	if w == os.Stdout {
+		cFprintf = color.New(color.FgRed).Fprintf
+	}
+
+	fmt.Fprintf(w, "[%s:%d] - ", fail.Path, fail.Line)
+	cFprintf(w, "%s\n", fail.Msg)
+	fmt.Fprintf(w, "\n%s\n%s\n\n", code, string(underLine))
+
+	return nil
+}
+
+func getLine(path string, line int) (string, error) {
+	fd, err := os.Open(path)
+	if err != nil {
+		return "", goerr.Wrap(err)
+	}
+	defer func() {
+		if err := fd.Close(); err != nil {
+			logger.Warn(err.Error())
+		}
+	}()
+
+	var idx int
+	scanner := bufio.NewScanner(fd)
+	for scanner.Scan() {
+		idx++
+		if idx == line {
+			return scanner.Text(), nil
+		}
+	}
+
+	return "", nil
+}
diff --git a/go.mod b/go.mod
index c36df5d..c03348d 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module github.com/m-mizutani/goast
 go 1.18
 
 require (
+	github.com/fatih/color v1.13.0
 	github.com/m-mizutani/goerr v0.1.7
 	github.com/m-mizutani/opac v0.1.2-0.20220911011947-30fd33506a09
 	github.com/m-mizutani/zlog v0.3.2
diff --git a/go.sum b/go.sum
index 5c6a50b..6e72219 100644
--- a/go.sum
+++ b/go.sum
@@ -22,6 +22,8 @@ github.com/dgraph-io/ristretto v0.1.0 h1:Jv3CGQHp9OjuMBSne1485aDpUkTKEcUqF+jm/Lu
 github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48 h1:fRzb/w+pyskVMQ+UbP35JkH8yB7MYb4q/qhBarqZE6g=
 github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48/go.mod h1:if7Fbed8SFyPtHLHbg49SI7NAdJiC5WIA09pe59rfAA=
 github.com/dustin/go-humanize v1.0.0 h1:VSnTsYCnlFHaM2/igO1h6X3HA71jcobQuxemgkq4zYo=
+github.com/fatih/color v1.13.0 h1:8LOYc1KYPPmyKMuN8QV2DNRWNbLo6LZ0iLs8+mlH53w=
+github.com/fatih/color v1.13.0/go.mod h1:kLAiJbzzSOZDVNGyDpeOxJ47H46qBXwg5ILebYFFOfk=
 github.com/fortytw2/leaktest v1.3.0 h1:u8491cBMTQ8ft8aeV+adlcytMZylmA5nnwwkRZjI8vw=
 github.com/foxcpp/go-mockdns v0.0.0-20210729171921-fb145fc6f897 h1:E52jfcE64UG42SwLmrW0QByONfGynWuzBvm86BoB9z8=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
@@ -58,8 +60,11 @@ github.com/m-mizutani/opac v0.1.2-0.20220911011947-30fd33506a09 h1:LXIbVjhcYSJP0
 github.com/m-mizutani/opac v0.1.2-0.20220911011947-30fd33506a09/go.mod h1:XLr1rba7h2qEUmOpVb1DKwOV1w3UvZP4q/zJWKtO1z0=
 github.com/m-mizutani/zlog v0.3.2 h1:gdtvmISolbikEt+9ZfP/WGOlzePQOYUWFisI+ZolUtQ=
 github.com/m-mizutani/zlog v0.3.2/go.mod h1:GxFJcc4bguQJIHXYOOBF16Of2+SIrPGlZ5JkdOECzyE=
+github.com/mattn/go-colorable v0.1.9/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
+github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/mattn/go-isatty v0.0.16 h1:bq3VjFmv/sOjHtdEhmkEV4x1AJtvUvOJ2PFAZ5+peKQ=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369 h1:I0XW9+e1XWDxdcEniV4rQAIOPUGDq67JSCiRCgGCZLI=
@@ -102,6 +107,9 @@ github.com/yashtewari/glob-intersection v0.1.0 h1:6gJvMYQlTDOL3dMsPF6J0+26vwX9MB
 github.com/yashtewari/glob-intersection v0.1.0/go.mod h1:LK7pIC3piUjovexikBbJ26Yml7g8xa5bsjfx2v1fwok=
 go.opencensus.io v0.23.0 h1:gqCw0LfLxScz8irSi8exQc7fyQ0fKQU/qnC/X8+V/1M=
 golang.org/x/net v0.0.0-20220325170049-de3da57026de h1:pZB1TWnKi+o4bENlbzAgLrEbY4RMYmUIRobMcSmfeYc=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220909162455-aba9fc2a8ff2 h1:wM1k/lXfpc5HdkJJyW9GELpd8ERGdnh8sMGL6Gzq3Ho=
 golang.org/x/sys v0.0.0-20220909162455-aba9fc2a8ff2/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=