The fact that there is blood in the ejaculate may be the result of acute injury, seminal vesiculitis, prostatitis and other factors. 1. Acute injury: non-degenerate blow or strenuous exercise, resulting in localized damage to the ejaculatory duct bleeding, in the ejaculation, there may be ejaculation stinging with blood sperm symptoms, may be localized in the lower body will also appear redness, pain, swelling and other symptoms. 2. Spermatitis: it may be related to the infection of neighboring organs, when the infection is aggravated, resulting in local damage to the seminal vesicles, which may cause ejaculatory stinging as well as hematospermia, and in severe cases, it may also cause male infertility. 3. Prostatitis: it may be related to unclean sex, frequent masturbation, poor hygiene and other factors, in the case of severe lesions may lead to ejaculatory stinging pain with bloody semen, accompanied by perineal swelling and pain, urinary frequency, urinary urgency and other symptoms. Ejaculation pain with bloody semen, indicating the existence of abnormal conditions, it is recommended to seek medical examination and treatment as soon as possible to avoid adverse effects.