diff --git a/condition/number_equal_to.go b/condition/number_equal_to.go
index f5accfff..465ed04d 100644
--- a/condition/number_equal_to.go
+++ b/condition/number_equal_to.go
@@ -39,13 +39,22 @@ func (insp *numberEqualTo) Condition(ctx context.Context, msg *message.Message)
 		return insp.match(f, compare), nil
 	}
 
+
+	val := msg.GetValue(insp.conf.Object.SourceKey)
+
+	// for gjson's GetValue, if the path is empty string (indicating source key or target key is not present),
+	// the Result.Exists() will return false
+	// If source or target key is present but value cannot be found, always return false
+	if !val.Exists() {
+		return false, nil
+	}
+
 	target := msg.GetValue(insp.conf.Object.TargetKey)
 	if target.Exists() {
 		compare = target.Float()
 	}
 
-	v := msg.GetValue(insp.conf.Object.SourceKey)
-	return insp.match(v.Float(), compare), nil
+	return insp.match(val.Float(), compare), nil
 }
 
 func (c *numberEqualTo) match(f float64, t float64) bool {
diff --git a/condition/number_equal_to_test.go b/condition/number_equal_to_test.go
index 91f264b0..3813baca 100644
--- a/condition/number_equal_to_test.go
+++ b/condition/number_equal_to_test.go
@@ -134,6 +134,70 @@ var numberEqualToTests = []struct {
 		[]byte(`{"foo": 100, "bar": 200}`),
 		false,
 	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "baz",
+				},
+				"value": 0,
+			},
+		},
+		[]byte(`{"foo": 100, "bar": 200}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "baz",
+					"target_key": "bar",
+				},
+			},
+		},
+		[]byte(`{"foo": 100, "bar": 200}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"target_key": "abc",
+				},
+			},
+		},
+		[]byte(`100`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "foo",
+					"target_key": "baz",
+				},
+			},
+		},
+		[]byte(`{"foo": 100, "bar": 200}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "baz",
+					"target_key": "abc",
+				},
+			},
+		},
+		[]byte(`{"foo": 100, "bar": 200}`),
+		false,
+	},
 }
 
 func TestNumberEqualTo(t *testing.T) {
diff --git a/condition/string_equal_to.go b/condition/string_equal_to.go
index 562ee614..7aa89eb3 100644
--- a/condition/string_equal_to.go
+++ b/condition/string_equal_to.go
@@ -40,14 +40,21 @@ func (insp *stringEqualTo) Condition(ctx context.Context, msg *message.Message)
 		return bytes.Equal(msg.Data(), compare), nil
 	}
 
-	target := msg.GetValue(insp.conf.Object.TargetKey)
+	val := msg.GetValue(insp.conf.Object.SourceKey)
 
+	// for gjson's GetValue, if the path is empty string (indicating source key or target key is not present),
+	// the Result.Exists() will return false
+	// If source or target key is present but value cannot be found, always return false
+	if !val.Exists() {
+		return false, nil
+	}
+
+	target := msg.GetValue(insp.conf.Object.TargetKey)
 	if target.Exists() {
 		compare = target.Bytes()
 	}
 
-	value := msg.GetValue(insp.conf.Object.SourceKey)
-	return bytes.Equal(value.Bytes(), compare), nil
+	return bytes.Equal(val.Bytes(), compare), nil
 }
 
 func (c *stringEqualTo) String() string {
diff --git a/condition/string_equal_to_test.go b/condition/string_equal_to_test.go
index 33785ca3..e6f004b6 100644
--- a/condition/string_equal_to_test.go
+++ b/condition/string_equal_to_test.go
@@ -73,6 +73,70 @@ var stringEqualToTests = []struct {
 		[]byte(`{"foo":"abc", "bar":"def"}`),
 		false,
 	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "foo",
+				},
+				"value": "abc",
+			},
+		},
+		[]byte(`{"bar": "abc", "baz": "0"}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "foo",
+				},
+				"value": "",
+			},
+		},
+		[]byte(`{"bar": "abc", "baz": "0"}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "foo",
+					"target_key": "baz",
+				},
+			},
+		},
+		[]byte(`{"bar": "abc", "baz": "0"}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"target_key": "foo",
+				},
+			},
+		},
+		[]byte(`{"bar": "abc", "baz": "0"}`),
+		false,
+	},
+	{
+		"fail",
+		config.Config{
+			Settings: map[string]interface{}{
+				"object": map[string]interface{}{
+					"source_key": "bar",
+					"target_key": "foo",
+				},
+			},
+		},
+		[]byte(`{"bar": "abc", "baz": "0"}`),
+		false,
+	},
 }
 
 func TestStringEqualTo(t *testing.T) {