When one side of the testicle becomes very small after testicular inflammation it is considered to be testicular atrophy, which is associated with necrosis of the testicular tissue structure and suspected to be chronic testicular inflammation. Orchitis is a common male disease, when one side of the testicle becomes very small after orchitis, it is considered to be a manifestation of testicular atrophy, which is most often seen clinically in chronic orchitis. Studies have shown that it may be because the testicles are stimulated by bacteria, viruses, mycoplasma and other pathogenic microorganisms, affecting the flow of testicular arteries, resulting in necrosis of testicular tissue and structure, followed by testicular atrophy, appearing on one side of the testicles become very small. In addition, the patient’s testicle may also be accompanied by mild tenderness, swelling and discomfort, and the texture of the testicle is obviously hardened. Patients with orchitis should pay attention to personal hygiene, keep the external genitalia clean and pay more attention to rest. In summary, testicular inflammation after one side of the testicle becomes very small patients need to go to the hospital in a timely manner, cooperate with the doctor to actively treat, so as not to continue to delay the condition, regular follow-up.