If the left testicle is swollen, it is recommended to go to the hospital for ultrasound examination of the testicle to clarify the cause and treat the symptoms for the fastest cure.1. If the patient has a history of mumps and the testicle is swollen secondary to it, the possibility of having viral orchitis should be considered. It is necessary to go to the hospital for relevant viral testing, and after the diagnosis is confirmed, it is recommended to give anti-viral treatment. Intravenous infusion of antiviral drugs is needed. For example, intravenous infusion of ribavirin 0.5g once a day for a week. Or use ganciclovir 0.25g, intravenous infusion, twice a day for one week. 2. It can also be seen in bacterial infections, such as secondary to urethral infection, epididymitis, etc., with acute testicular enlargement. It is recommended to perform ultrasound examination of the testicles and routine blood and urine tests, and after the infection is diagnosed, intravenous antibiotic treatment is required. The drug can be cefoxitin sodium 2.0g for injection, intravenous drip, twice a day for a week. 3, also exclude the presence of testicular tumor. If you have testicular tumor, you need to perform CT examination of testis and testicular tumor indicator examination. If CT of testis suggests tumor and tumor indexology suggests a high possibility of tumor, radical orchiectomy is recommended.