To evaluate the training effect in cataract surgery, we studied four right-handed ophthalmologists who were learning temporal corneal incision. The surgical technique included phacoemulsification of cataractous lens nuclei with an ultrasonic handpiece and insertion of intraocular lenses with the right hand for the right eye and with the left hand for the left eye. We recorded the ultrasound time and energy to evaluate the training process quantitatively and compared 10 early cases with 10 cases treated after 6 to 15 months of training. We found that ultrasound time decreased after training and did not differ significantly between the right and left hands for three trainees. However, one trainee continued to require longer ultrasound time with the left hand even after training. The reduction in energy was greatest for the youngest trainee, indicating the training effect was also greatest. We could evaluate the training process quantitatively and could determine individual characteristics for a standardized technique, such as phacoemulsification in cataract surgery.