The author in his analysis focuses on two subjects. The first one is the history of legal gender recognition as a European standard followed by the analysis of the connections between legal gender recognition and the right to have medical treatment reimbursed by insurance, right to marriage, right to have children and protection against discrimination. The second one is related to the analysis of the margin of appreciation that States-Parties to the Convention enjoy in regulating conditions for the admissibility to request the recognition of one’s gender identity. Presented analysis lead to a conclusion that European standard of legal gender recognition is defined in negative way by limiting the margin of appreciation that States-Parties to the Convention enjoy in regulating conditions for the admissibility to request the recognition of one’s gender identity.