Transsexualism is a serious reversal of sexual identity, which usually develops at the age of 3 years old, with psychological inversion during adolescence. “They strongly demand to change their sexual anatomy and request sex reassignment surgery to achieve their beliefs. When their demands for easy sex are not satisfied, they often suffer from internal conflicts, which may even lead to self-harm or self-murder. The causes are complex and may be related to the following factors: genetics, endocrine, external genital size and morphology, environmental and psychological factors, and abnormal function of the gender center. Transsexualism is characterized by a lifelong feeling of being a member of the opposite sex, heterosexual sexual behavior and cross-dressing that does not cause eroticism, a deep distaste for genitalia from which no pleasure can be derived, and an aversion to homosexual behavior. Transsexualism needs to be distinguished from transvestism, homosexuality and schizophrenia, which have common causes and behavioral manifestations, but are substantially different. The fundamental difference between transvestism, transvestism and homosexuality is whether or not the person is asking for a sex change. Transsexuals dress in the form of cross-gender clothing to make their appearance conform to their conscious gender, and cross-gender dress without the goal of sexual arousal, only to achieve psychological balance, not to pursue sexual relationships, let alone sexual behavior abnormalities. People who are prone to sexually transmitted diseases have a disorder of self-identification with gender, identify themselves as the opposite sex, and desire to change their biological sex. Some people, as adults, take themselves as the opposite sex to love people of the other sex, and both sides treat each other with understanding, sympathy, sincere attitude and noble requirements, and generally do not do immoral or illegal things, nor simply pursue sexual behavior, which is more in female transvestites, and we name it as homosexual heterosexuality. 1, transvestites are positive about their biological sex, and no request for sex change, attribute behavior abnormalities, mostly seen in men, sexually oriented to the opposite sex, interested in sexual intercourse, dressed in heterosexual clothing with sexual pleasure-seeking components, and even sexual excitement or sexy satisfaction. Occasionally, there are people who ask for sex change, but after understanding the essence of sex change surgery, they mostly avoid it and stop seeking medical treatment. There is a transvestite; get his wife’s approval, monthly cross-dressing, dressed as a woman shopping once, and family sexual relations are normal, recently informed that he still has foot-binding fetish, appreciate the female three inch golden lotus, after more than 7 years of interaction and observation, its a typical transvestite patients, and I am very good in the work of lawyers. 2. Homosexuals identify with their own gender, have no transgender requirements, are sexually oriented towards the same sex, are feeling for others, and take same-sex individuals as sexual objects. Homosexuals are mostly men, they have their own circle of life, often grouped into groups of activities in parks, public toilets, public baths, sodomy as a way to sex, most people play the active, passive two roles, sexual behavior is completely cathartic sexual desire, fixed homosexual couples are rare. Homosexuals are not willing to dress in cross-dressing, even if they are pretending to be a party of heterosexual posture, still focusing on homosexuality, not to mention the desire to change sex. Most female homosexuals are emotional, they love each other very much, sometimes it is not easy to distinguish from easy sex disease, and still need to be studied and screened in depth. 3. Patients with schizophrenia, some of whom also have transsexual delusions, are delusional about becoming members of the opposite sex and see easy sex surgery as a magical cure. They avoid confronting the focus of their problem. Some men are paranoid and delusional about having children after sex change, some delusional about becoming famous singers, and some demand testicle removal to eliminate their beards. They do not have a huge psychological conflict between their sexual identity and their biological sex, nor do they have a consistent medical history. When they are not satisfied with sex change, they may lose their senses in a state of irritation and excitement, hit and scold their relatives, threaten to kill, and show mild schizophrenic paranoia. These should be carefully analyzed in the medical history, and can be correctly judged from the different eyes of the treatment seeker. Sex reassignment surgery refers to changing the original external genitalia into a heterosexual structure and removing the gonads. The hallmark surgeries are vaginal rejuvenation and penile rejuvenation. At the same time, superficial reshaping, such as laryngeoplasty and mammoplasty, is performed to conform to self-perceived gender re-identification. After surgery, the patient’s original contradiction between self-perceived gender and biological gender is relieved, psychological balance is achieved, sexual function returns to normal, and he or she can marry and form a family, but has no fertility. Male to female surgery includes orchidopexy, urethroplasty, labiaplasty, vaginal reconstruction, laryngeoplasty, and breast augmentation. Female-to-male surgery is more complex and difficult and includes mastectomy and nipple reconstruction,, removal of internal genitalia (ovaries, fallopian tubes, uterus and vagina), and penile reconstruction (urethral formation, support tissue implantation, and stem formation). Strict clinical procedures and systems have been developed for sex reassignment surgery, which must address and take into account many complex social issues, and must have various certificates and be carefully reviewed. After the diagnosis is clear and the conditions are fully available, the decision to perform sex reassignment surgery can only be made after validation by the relevant authorities. Before the relevant laws and regulations were published, strict procedures and systems were established for sex reassignment surgery in clinical practice since 1992. 1.Patients must solve and consider many complicated social problems before the surgery, such as work, life, economic source, family composition, social opinion after the surgery, etc. 2.The surgery is preceded by an adaptation process and a trial of heterosexual behavior and roles in daily life for 1 to 2 years. 3.The following certificates must be available: ① Proof from the public security department, which should obtain the understanding and recognition of the public security department, and the gender and proof of citizenship in the account book should be replaced after the operation; ② Personal application, including experience, medical history, family situation, operation requirements and determination; ③ Proof from the psychiatric hospital to exclude mental illness; ④ Proof from parents and siblings to seek the understanding and recognition of family members after the operation; ⑤ Work unit Certificate, post-operative work arrangement and economic source; ⑥Certificate from township government and neighborhood committee to obtain social recognition and understanding; ⑦Married person must solve the spouse problem and have a court certificate; ⑧Preparation of medical expenses and post-operative life security measures. 4. All the above certificates should be carefully examined. After the diagnosis is clear and the conditions are fully available, the decision of whether to perform sex reassignment surgery can be made only after the relevant departments have validated it.