Penile erection can be elicited by various stimuli integrated in the spinal cord and/or higher central nervous structures. The medial preoptic area (MPOA) of the hypothalamus is known to play a key role in the regulation of the male sexual behavior. In anesthetized male rats we performed MPOA stimulation via stereotaxically implanted electrodes or canulae delivering L-glutamate. An erectile response, assessed by an increase of intracavernous pressure (ICP), was recorded during electrical stimulation of the MPOA. Stimulating the posterior region of the MPOA elicited a greater erectile response than stimulation applied to the anterior region. Microinjections of L-glutamate also elicited an ICP increase. Stimulation of MPOA neurons therefore elicits activation of neural pathways controlling penile erection.