The sex of a person is assigned at birth. Later some people — intersex persons and transsexuals — experience the problems with a legal gender and seek to change the entry of birth, certificate of birth and other documents. This article has been written under the impulse from case S. (post surgery transsexual) which has been considered by Russian courts. Neither the registrar’s office nor courts allowed S. to make change in his entry of birth. As result he faces total discrimination on the grounds of gender identity. As it is known, applications of two transsexuals — No. 86501/12 (Y. P. v. Russia) and the Application No. 60796/16 (X. v. Russia) — were communicated to the Russian Government by the ECHR on 23 February 2017. This article explains the meaning of legal gender, reasons of its change, the procedure of amending the entry of birth in such case in Russia and shows that the registrar’s office and courts put forward unfounded arbitrary conditions due to gaps in legislation and ignore the right of a person to the legal recognition of his or her gender identity. International legal approaches to the realization of this right are highlighted with emphasis on the ECHR positions. The examples of contemporary foreign legislation on the gender recognition including the attitude to forced divorce and new approach to the entry of birth in case of birth of intersex child to prevent premature medical intervention contrary to the gender self-identification of such a child are given.