diff --git a/styles_test.go b/styles_test.go
new file mode 100644
index 0000000..7a7e228
--- /dev/null
+++ b/styles_test.go
@@ -0,0 +1,134 @@
+package excelize
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSetConditionalFormat(t *testing.T) {
+	cases := []struct {
+		label  string
+		format string
+		rules  []*xlsxCfRule
+	}{{
+		label: "3_color_scale",
+		format: `[{
+			"type":"3_color_scale",
+			"criteria":"=",
+			"min_type":"num",
+			"mid_type":"num",
+			"max_type":"num",
+			"min_value": "-10",
+			"mid_value": "0",
+			"max_value": "10",
+			"min_color":"ff0000",
+			"mid_color":"00ff00",
+			"max_color":"0000ff"
+		}]`,
+		rules: []*xlsxCfRule{{
+			Priority: 1,
+			Type:     "colorScale",
+			ColorScale: &xlsxColorScale{
+				Cfvo: []*xlsxCfvo{{
+					Type: "num",
+					Val:  -10,
+				}, {
+					Type: "num",
+					Val:  0,
+				}, {
+					Type: "num",
+					Val:  10,
+				}},
+				Color: []*xlsxColor{{
+					RGB: "FFFF0000",
+				}, {
+					RGB: "FF00FF00",
+				}, {
+					RGB: "FF0000FF",
+				}},
+			},
+		}},
+	}, {
+		label: "3_color_scale default min/mid/max",
+		format: `[{
+			"type":"3_color_scale",
+			"criteria":"=",
+			"min_type":"num",
+			"mid_type":"num",
+			"max_type":"num",
+			"min_color":"ff0000",
+			"mid_color":"00ff00",
+			"max_color":"0000ff"
+		}]`,
+		rules: []*xlsxCfRule{{
+			Priority: 1,
+			Type:     "colorScale",
+			ColorScale: &xlsxColorScale{
+				Cfvo: []*xlsxCfvo{{
+					Type: "num",
+					Val:  0,
+				}, {
+					Type: "num",
+					Val:  50,
+				}, {
+					Type: "num",
+					Val:  0,
+				}},
+				Color: []*xlsxColor{{
+					RGB: "FFFF0000",
+				}, {
+					RGB: "FF00FF00",
+				}, {
+					RGB: "FF0000FF",
+				}},
+			},
+		}},
+	}, {
+		label: "2_color_scale default min/max",
+		format: `[{
+			"type":"2_color_scale",
+			"criteria":"=",
+			"min_type":"num",
+			"max_type":"num",
+			"min_color":"ff0000",
+			"max_color":"0000ff"
+		}]`,
+		rules: []*xlsxCfRule{{
+			Priority: 1,
+			Type:     "colorScale",
+			ColorScale: &xlsxColorScale{
+				Cfvo: []*xlsxCfvo{{
+					Type: "num",
+					Val:  0,
+				}, {
+					Type: "num",
+					Val:  0,
+				}},
+				Color: []*xlsxColor{{
+					RGB: "FFFF0000",
+				}, {
+					RGB: "FF0000FF",
+				}},
+			},
+		}},
+	}}
+
+	for _, testCase := range cases {
+		xl := NewFile()
+		const sheet = "Sheet1"
+		const cellRange = "A1:A1"
+
+		err := xl.SetConditionalFormat(sheet, cellRange, testCase.format)
+		if err != nil {
+			t.Fatalf("%s", err)
+		}
+
+		xlsx := xl.workSheetReader(sheet)
+		cf := xlsx.ConditionalFormatting
+		assert.Len(t, cf, 1, testCase.label)
+		assert.Len(t, cf[0].CfRule, 1, testCase.label)
+		assert.Equal(t, cellRange, cf[0].SQRef, testCase.label)
+		assert.EqualValues(t, testCase.rules, cf[0].CfRule, testCase.label)
+	}
+}