To evaluate methods of prevention of scrotal hyperthermia in laptop computer (LC) users.Experimental study.University hospital.Twenty-nine healthy male volunteers.Right and left scrotal temperature and LC and lap pad temperatures were recorded during three separate 60-minute sessions using a working LC in a laptop position: session 1, sitting with closely approximated legs; session 2, sitting with closely approximated legs with a lap pad below the working LC; and session 3, sitting with legs apart at a 70° angle with a lap pad below the working LC.Scrotal temperature elevation.Scrotal temperature increased significantly regardless of leg position or use of a lap pad. However, it was significantly lower in session 3 (1.41°C ± 0.66°C on the left and 1.47°C ± 0.62°C on the right) than in session 2 (2.18°C ± 0.69°C and 2.06°C ± 0.72°C) or session 1 (2.31°C ± 0.96°C and 2.56°C ± 0.91°C). A scrotal temperature elevation of 1°C was reached at 11 minutes in session 1, 14 minutes in session 2, and 28 minutes in session 3.Sitting position with closely approximated legs is the major cause of scrotal hyperthermia. Scrotal shielding with a lap pad does not protect from scrotal temperature elevation. Prevention of scrotal hyperthermia in LC users presently is not feasible. However, scrotal hyperthermia may be reduced by a modified sitting position (legs apart) and significantly shorter use of LC.