diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 506ef68c..19770c9f 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 ## v0.3.0 (2021-12-22)
 
-- feat: implement transaction mechanism for load test
+- feat: implement `transaction` mechanism for load test
 - feat: support `--continue-on-failure` flag to continue running next step when failure occurs, default to failfast
 - refactor: fork [boomer] as sub module
 - feat: report GA events with version
diff --git a/examples/demo.json b/examples/demo.json
index 4f371a05..0f6c9819 100644
--- a/examples/demo.json
+++ b/examples/demo.json
@@ -11,6 +11,13 @@
         }
     },
     "teststeps": [
+        {
+            "name": "transaction 1 start",
+            "transaction": {
+                "name": "tran1",
+                "type": "start"
+            }
+        },
         {
             "name": "get with params",
             "request": {
@@ -64,6 +71,13 @@
                 }
             ]
         },
+        {
+            "name": "transaction 1 end",
+            "transaction": {
+                "name": "tran1",
+                "type": "end"
+            }
+        },
         {
             "name": "post json data",
             "request": {
diff --git a/examples/demo.yaml b/examples/demo.yaml
index 0bc18920..a0cee432 100644
--- a/examples/demo.yaml
+++ b/examples/demo.yaml
@@ -8,6 +8,10 @@ config:
         varFoo1: ${gen_random_string($n)}
         varFoo2: ${max($a, $b)}
 teststeps:
+    - name: transaction 1 start
+      transaction:
+        name: tran1
+        type: start
     - name: get with params
       request:
         method: GET
@@ -43,6 +47,10 @@ teststeps:
           assert: equals
           expect: "34.5"
           msg: check args foo2
+    - name: transaction 1 end
+      transaction:
+        name: tran1
+        type: end
     - name: post json data
       request:
         method: POST
diff --git a/examples/demo_test.go b/examples/demo_test.go
index 0fb4e566..bb41544e 100644
--- a/examples/demo_test.go
+++ b/examples/demo_test.go
@@ -18,6 +18,7 @@ var demoTestCase = &hrp.TestCase{
 			"varFoo2": "${max($a, $b)}", // 12.3; eval with built-in function
 		}),
 	TestSteps: []hrp.IStep{
+		hrp.NewStep("transaction 1 start").StartTransaction("tran1"), // start transaction
 		hrp.NewStep("get with params").
 			WithVariables(map[string]interface{}{ // step level variables
 				"n":       3,                // inherit config level variables if not set in step level, a/varFoo1
@@ -35,6 +36,7 @@ var demoTestCase = &hrp.TestCase{
 			AssertLengthEqual("body.args.foo1", 5, "check args foo1").            // validate response body with jmespath
 			AssertLengthEqual("$varFoo1", 5, "check args foo1").                  // assert with extracted variable from current step
 			AssertEqual("body.args.foo2", "34.5", "check args foo2"),             // notice: request params value will be converted to string
+		hrp.NewStep("transaction 1 end").EndTransaction("tran1"), // end transaction
 		hrp.NewStep("post json data").
 			POST("/post").
 			WithBody(map[string]interface{}{
diff --git a/examples/demo_test.py b/examples/demo_test.py
new file mode 100644
index 00000000..e2eddc1f
--- /dev/null
+++ b/examples/demo_test.py
@@ -0,0 +1,63 @@
+# NOTE: Generated By HttpRunner v3.1.6
+# FROM: hrp/examples/demo.json
+
+
+from httprunner import HttpRunner, Config, Step, RunRequest, RunTestCase
+
+
+class TestCaseDemo(HttpRunner):
+
+    config = (
+        Config("demo with complex mechanisms")
+        .variables(
+            **{
+                "a": 12.3,
+                "b": 3.45,
+                "n": 5,
+                "varFoo1": "${gen_random_string($n)}",
+                "varFoo2": "${max($a, $b)}",
+            }
+        )
+        .base_url("https://postman-echo.com")
+    )
+
+    teststeps = [
+        Step(
+            RunRequest("get with params")
+            .with_variables(**{"b": 34.5, "n": 3, "varFoo2": "${max($a, $b)}"})
+            .get("/get")
+            .with_params(**{"foo1": "$varFoo1", "foo2": "$varFoo2"})
+            .with_headers(**{"User-Agent": "HttpRunnerPlus"})
+            .extract()
+            .with_jmespath("body.args.foo1", "varFoo1")
+            .validate()
+            .assert_equal("status_code", 200)
+            .assert_equal('headers."Content-Type"', "application/json")
+            .assert_equal("body.args.foo1", 5)
+            .assert_equal("$varFoo1", 5)
+            .assert_equal("body.args.foo2", "34.5")
+        ),
+        Step(
+            RunRequest("post json data")
+            .post("/post")
+            .validate()
+            .assert_equal("status_code", 200)
+            .assert_equal("body.json.foo1", 5)
+            .assert_equal("body.json.foo2", 12.3)
+        ),
+        Step(
+            RunRequest("post form data")
+            .post("/post")
+            .with_headers(
+                **{"Content-Type": "application/x-www-form-urlencoded; charset=UTF-8"}
+            )
+            .validate()
+            .assert_equal("status_code", 200)
+            .assert_equal("body.form.foo1", 5)
+            .assert_equal("body.form.foo2", "12.3")
+        ),
+    ]
+
+
+if __name__ == "__main__":
+    TestCaseDemo().test_start()
diff --git a/step.go b/step.go
index 5cbc296e..4bfcc167 100644
--- a/step.go
+++ b/step.go
@@ -174,6 +174,28 @@ func (s *StepRequest) CallRefCase(tc *TestCase) *StepTestCaseWithOptionalArgs {
 	}
 }
 
+// StartTransaction starts a transaction.
+func (s *StepRequest) StartTransaction(name string) *StepTransaction {
+	s.step.Transaction = &Transaction{
+		Name: name,
+		Type: TransactionStart,
+	}
+	return &StepTransaction{
+		step: s.step,
+	}
+}
+
+// EndTransaction ends a transaction.
+func (s *StepRequest) EndTransaction(name string) *StepTransaction {
+	s.step.Transaction = &Transaction{
+		Name: name,
+		Type: TransactionEnd,
+	}
+	return &StepTransaction{
+		step: s.step,
+	}
+}
+
 // StepRequestWithOptionalArgs implements IStep interface.
 type StepRequestWithOptionalArgs struct {
 	step *TStep