This study examined the impact of Blended learning on electrical machinery learning, as measured by both learning achievement and self-perceived effects. The subjects were two classes of second-year vocational high school students who takes electrical-machinery course in the department of Electrical Technology. There were 33 students in an experimental group and 32 students in a control group. The experimental group used Blended learning and the control group used traditional learning. The experiment lasted for 5 weeks. The results were as follows: (1) Blended learning had no impact on learning achievement. (2) Compares with the traditional learning, Blended learning had a significant impact on self-perceived effects. These effects ranked in decreasing order of importance which are cognitive and skill. (3) There was a significant difference in self-perceived effect (cognitive, skill, and affective) for experimental group.