diff --git a/parser.go b/parser.go
new file mode 100644
index 00000000..48ec28d7
--- /dev/null
+++ b/parser.go
@@ -0,0 +1,29 @@
+package httpboomer
+
+import (
+	"log"
+	"net/url"
+)
+
+func parseStep(step IStep, config *TConfig) *TStep {
+	tStep := step.ToStruct()
+	tStep.Request.URL = buildURL(config.BaseURL, tStep.Request.URL)
+	return tStep
+}
+
+func buildURL(baseURL, stepURL string) string {
+	uConfig, err := url.Parse(baseURL)
+	if err != nil {
+		log.Fatalf("[buildURL] baseURL: %v, error: %v", baseURL, err)
+		return ""
+	}
+
+	uStep, err := uConfig.Parse(stepURL)
+	if err != nil {
+		log.Fatalf("[buildURL] baseURL: %v, error: %v", baseURL, err)
+		return ""
+	}
+
+	// base url missed
+	return uStep.String()
+}
diff --git a/parser_test.go b/parser_test.go
new file mode 100644
index 00000000..5e1b67ac
--- /dev/null
+++ b/parser_test.go
@@ -0,0 +1,29 @@
+package httpboomer
+
+import (
+	"testing"
+)
+
+func TestBuildURL(t *testing.T) {
+	var url string
+	url = buildURL("https://postman-echo.com", "/get")
+	if url != "https://postman-echo.com/get" {
+		t.Fatalf("buildURL error, %s != 'https://postman-echo.com/get'", url)
+	}
+
+	url = buildURL("https://postman-echo.com/abc/", "/get?a=1&b=2")
+	if url != "https://postman-echo.com/get?a=1&b=2" {
+		t.Fatalf("buildURL error, %s != 'https://postman-echo.com/get'", url)
+	}
+
+	url = buildURL("", "https://postman-echo.com/get")
+	if url != "https://postman-echo.com/get" {
+		t.Fatalf("buildURL error, %s != 'https://postman-echo.com/get'", url)
+	}
+
+	// notice: step request url > config base url
+	url = buildURL("https://postman-echo.com", "https://httpbin.org/get")
+	if url != "https://httpbin.org/get" {
+		t.Fatalf("buildURL error, %s != 'https://httpbin.org/get'", url)
+	}
+}
diff --git a/runner.go b/runner.go
index 4196d74f..2362ab3a 100644
--- a/runner.go
+++ b/runner.go
@@ -44,12 +44,6 @@ func (r *Runner) runCase(testcase *TestCase) error {
 	return nil
 }
 
-func parseStep(step IStep, config *TConfig) *TStep {
-	tStep := step.ToStruct()
-	tStep.Request.URL = config.BaseURL + tStep.Request.URL
-	return tStep
-}
-
 func (r *Runner) runStep(step *TStep) error {
 	log.Printf("run step begin: %v >>>>>>", step.Name)
 	var v []interface{}