At present, there is no particularly safe and effective way to enlarge the penis; for the small penis caused by low testosterone level in the body, you can consider applying medication such as methyltestosterone tablets to treat it; for the small penis caused by other reasons, you can consider surgery to treat it. 1. Low testosterone level: It is one of the most important causes of small penis, which can lead to the patient’s small and short penis. Patients can apply medications such as methyltestosterone tablets and testosterone undecanoate under the guidance of doctors for treatment, which can improve the symptoms of small penis and serve the purpose of thickening. After using the medication, patients may experience adverse reactions such as sodium retention and jaundice, which should be disposed of by a doctor in time. Children and elderly patients should be cautious application, avoid long-term application. 2. Other factors: such as congenital penile thinness, penile deformity and other causes of penile thinness, can take prosthesis implantation, penile lengthening surgery and other ways of treatment, as appropriate. The causes and degree of penile smallness in men are different, and the corresponding treatment measures must be taken after consulting a doctor to confirm the diagnosis and follow the doctor’s advice.