Based on lateral hypothalamic self-stimulation behavior of the rat in a Skinner box, a “conflict” situation was established by combining foot shock punishment with brain stimulation. Diazepam (10–20 mg/kg, PO) caused a marked increase in the lever pressing response in the punished period without affecting the unpunished response. Bromazepam (10–20 mg/kg PO) also caused an increase in the lever pressing response in the punished period and a decrease of the punished response. These results indicate that a “conflict” situation based on self-stimulation behavior is useful for the evaluation of antianxiety action.