At present, it is believed that the effects of antipsychotic drugs on male sexual function extend throughout the entire sexual response cycle, i.e., they have different degrees of effects on the three stages of sexual desire, sexual arousal and orgasm; in the stage of sexual desire, antipsychotic drugs will lead to low sexual desire or lack of sexual desire; in the stage of sexual arousal, they will lead to erectile dysfunction or abnormal erection; in the stage of orgasm, they will lead to delayed ejaculation or reverse ejaculation. The mechanism of the effect of antipsychotic drugs on erectile function is not clear, but it is mainly considered to be closely related to their anticholinergic effect, which causes the relaxation of the detrusor muscle, resulting in difficulty in urination; moreover, the adrenergic α1 receptors in the drugs can cause penile vasodilation and abnormal filling of the corpus cavernosum, while venous closure can inhibit blood return, resulting in abnormal erection. In addition, it has been suggested that nitric oxide (NO) and its synthase (NOS) in penile vascular and cavernous tissues play an important role in penile erection, and antipsychotic drugs affect the function of NO and NOS in the central nervous system and inhibit their synthesis to induce penile erection. In conclusion, erectile dysfunction is a common drug side effect of antipsychotic drugs, and the clinical manifestations of patients should be closely observed during medication and treated in a timely manner in order to improve the therapeutic effect and medication safety.