This study develops a multimedia computer-assisted instruction (CAI) system for training in intramuscular injection. The multimedia, webpage design and computer graphics technologies are integrated not only to provide static nursing knowledge, but also to present interactive learning content needed for instruction in clinical intramuscular injection. The content of the system is adapted from current standard clinical procedures. Students can acquire knowledge and skill in intramuscular injection by interactive participation in safe, convenient and harmless skill training. Those are new to the nursing profession can acquire training in intramuscular injection skills and knowledge more efficiently by using the multimedia CAI system.