This invention provides the application of lecithin in the preparation of drugs for the prevention and / or treatment of infertility, belonging to the field of biomedical preparation technology. Specifically, it relates to the application of lecithin in the preparation of drugs for the prevention and / or treatment of infertility, recurrent miscarriage, and / or uterine decidualization disorders. The lecithin can effectively reduce TNF-α levels in early pregnancy, improve uterine decidualization disorders, and increase endometrial receptivity, thereby increasing pregnancy rates and providing a new approach for the treatment of infertility and recurrent miscarriage.