This research aims to develop and calculate the efficiency of electronic books injection mold design engineering for Plastic Mold Technology1 (04-812-313) The participants of this research were 40 third year students who enrolled in Plastic Mold Technology1 subjects in first semester 2013. The research tools were 1) an electronic books 2) a questionnaire for measure an efficiency of electronic books 3) an achievement test. Data were analyzed by using difficulty discrimination validity index of consistency The result showed that quality of electronic books injection mold design engineering was in a very good level with higher sufficiency mean = 1.13 than criteria at mean = 1 and was very useful for Plastic Mold Technology1 (04-812-313)