Semen is the product of the mixing of sperm and seminal plasma, and is the result of the joint collaboration of the male reproductive glands. The organic component is mainly sperm, but also contains testicular cells, columnar epithelial cells, lymphocytes, protein particles, prostatic lecithin vesicles, spermatozoa crystals, etc. These components account for 10% of the total semen, and seminal plasma accounts for about 90%, mainly water and some inorganic salts, proteins, enzymes, i.e., semen secreted by the prostate gland and secretions from the epididymis, seminal vesicles, urethral bulb glands, and paraurethral glands. Fresh semen is a grayish-white viscous liquid with a special odor. The amount of ejaculate at one time is related to the age of the individual and the frequency of ejaculation, generally 2 to 6 ml, containing 60 to 20 million sperm per ml. The human mature sperm is tadpole-like, with a head 3 to 5 microns long, 2 to 3 microns wide, and 1 to 2 microns thick. The middle length is about 6 microns, the tail length is 40-50 microns, and the total length is 50-60 microns. The anterior part of the sperm head is a vacuole and the posterior part is a dense cell nucleus. The head has a flattened oval-like shape in lateral view and a pear-shaped shape in frontal view. A sperm count of less than 50 million sperm per milliliter of semen is considered spermopenia. Any sperm with poor motility accounting for more than 50%, deformed sperm accounting for more than 10%, or total semen less than 1 ml are considered abnormal. The quality of semen is directly related to fertility, and the result of routine semen examination is an important indicator to evaluate male fertility. The results of semen examination are of great value in evaluating male fertility, and the results are easily affected by many factors such as frequency of semen discharge, collection integrity, container and temperature. The correct collection method should be noted as follows: 1. Abstinence for 3 to 7 days for sperm retrieval. Abstinence time is too short to affect the sperm density, too long to lead to excessive dead sperm, abnormal sperm rate and so on. 2. Semen must be collected intact. The first part of the semen discharge has the highest sperm density, and the loss of this part of the semen will seriously affect the test results. 3, with a wide mouth bottle collection is preferred, ordinary condoms because of the spermicidal substances, should not be used. 4, the specimen transport process should be 37 ℃ is appropriate, and should be delivered within half an hour.