The left side of the scrotum pain in the urine, may be caused by prostatitis, usually associated with bad habits, unclean sex, neighboring organs infection and other factors. 1. Bad habits: irregular work and rest, long time drinking and smoking, long time consuming stimulating food, long time holding urine and other factors, may induce prostatitis, can lead to the left side of the scrotum pain and urine dripping. 2. Unclean sex: frequent and unclean sex can lead to prostatitis, which usually causes urinary dribbling, incomplete urination, frequent urination, scrotal pain and other symptoms. 3. Neighboring organ infections: for example, seminal vesiculitis, due to the presence of infection in the seminal vesicles, improper care, the infection aggravated, can induce prostatitis, can lead to the left side of the scrotum pain as well as urinary dribbling.