We evaluated a commercially produced head-mounted display (HMD) to determine its short-term effects on human ocular accommodation. Thirteen subjects (seven men and six women, ranging from 13 to 44 years old) were tested for changes in a number of parameters before and after viewing a full-length movie (approximately two hours) on a HMD. As a control, subjects were also tested before and after viewing a movie on a high-quality NTSC color television, and also before and after a one-hour intermission. Accommodation dynamics and range were measured. Data showed wellknown trends due to subject age. Only one statistically significant change was found: a slight increase in the latency of relaxation accommodation after HMD viewing.