The disclosed embodiments provide a method, a server, and a terminal device for establishing a communication session. The method includes: receiving a communication session request sent from a first user via a terminal device; obtaining a communication session target for the first user, a second user, by matching for the first user; and sending an identifier of the second user to the terminal device to establish a communication session between the first user and the second user, wherein the identifier is used for the terminal device to distinguish the communication session target of the first user, and is hidden from the first user.