An inexpensive, individual mouse urine collection apparatus was constructed from a 250 ml conical polypropylene centrifuge tube and wire cloth. The construction did not require special tools, and was completed in 1 hour. This apparatus allowed the ad libitum feeding and watering of individual mice during the urine collection period. Volumes of urine collected ranged from 0.5-2.0 ml per 24 hours per 25 g mouse.