The reason for bleeding the day after sex for men may be the following: 1. In most cases, it is caused by a tear in the penile tether, usually due to excessive force during sex, or improper methods of sex. It is best to prohibit sex in the near future to avoid aggravation of the tear. 2, due to the symptoms of hemorrhagic sperm, hemorrhagic sperm is mostly caused by too many times of sexual life, or no sexual life for a long time. The actual fact is that you will need to have a good routine and abstain from spicy food. 3, also do not exclude the phenomenon of kidney yin deficiency. So the causes of bleeding after sex are many, it is best to go to the hospital to do a targeted examination, timely face to face doctor for treatment.