The 11-year-old child has relatively small genitals relatively late development and other physiological factors, but also may be hidden penis, androgen deficiency and other pathological factors, can be temporarily observed, medication, and surgical treatment and so on. 1. Physiological factors: 11-year-old children’s genitals may be small because they have not yet entered the development stage or development is relatively late, just need to maintain good nutritional intake of children, maintain a good work and rest, participate in physical exercise, pay attention to the observation of the child’s secondary sexual characteristics of the changes in the temporary observation, without special treatment. 2. Pathological factors: (1) Hidden penis: usually because the penis cannot be exposed, making the appearance of the penis look relatively small. It can be observed temporarily, and if it still cannot recover by itself after puberty, it can be treated by surgery, supplemented by weight loss. (2) Androgen deficiency: Androgen plays an important role in promoting the development of the first male sex characteristics, which can promote the testicles to become bigger and the penis to become thicker. If androgen is low during the growth and development period, the phenomenon of small penis may occur. It can be treated by consuming foods such as squid, shrimp, loach and, if necessary, exogenous androgens such as methyltestosterone and testosterone supplementation. Through observation and treatment, the genitals are still stunted, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment.