In order to develop a more adequate ultraviolet (UV)-induced cataract model, a combination of l-buthionine sulfoximine (BSO) treatment was applied to experimental animals. A single administration of BSO 4 mmol/kg caused reduced glutathione concentration until experimental day 8. In the 0.067-J/cm2 UV-B irradiation experiment, the light-scattering intensity of the anterior lens cortex of the combination group was significantly higher than that of the other groups during the second week after irradiation commenced. After the fourth experimental week, however, there was no significant difference between the group treated by UV-B alone and the combination group. In the 0.2-J/cm2 UV-B irradiation experiment, anterior polar cataract was seen in the group receiving UV-B alone, as already reported, 6 weeks after starting UV irradiation. Meanwhile, in the combination group, shallow cortical opacity was seen at 26 weeks after the start of experiment in the deeper lenticular layer which was separated from the anterior subcapsular opacity. This anterior shallow cortical opacity seemed to move towards the nuclear region during the time course of the experiment. The results of this experiment suggested that the BSO treatment accelerated cataractogenesis through additional UV-B irradiation. Although more experiments are needed, this model is useful in investigating the connection between UV-B and other cocataractogenic factors in age-related cataract in humans.