You can improve your penis hardness by exercising your pubicococcygeus muscle, squatting, eating more seafood and zinc-rich foods, and taking medications such as sildenafil. 1. Exercise pubococcygeus muscle: pubococcygeus muscle, also called PC muscle, is a group of muscles in the human pubic area. the strength and elasticity of the PC muscle is very important for sexual intercourse to enhance the sexual response, exercise pubococcygeus muscle can improve the hardness of the penis. 2. Squatting horse stance: this action can fully exercise the buttocks, deep pelvis and thigh muscles. Practicing 15 minutes a day can make men less fatigued during sex. 3. Eat more seafood and zinc-rich food: male semen contains a high concentration of zinc, which can ensure men’s sexual function, so eat more seafood and zinc-rich food can promote male function. 4. Drug treatment: including sildenafil and other drugs to improve the symptoms of penile erection is not hard, the drug should be applied under the guidance of the doctor. If the patient is not feeling well, he should consult the doctor for examination and early treatment.