An RF MEMS switch using a fine liquid metal droplet is provided. The RF MEMS switch using a fine liquid metal droplet includes: a first layer member having a signal transmission line; a second layer member disposed on the first layer member, and having a chamber formed corresponding to the signal transmission line so as to induce a change in the shape of the fine liquid metal droplet and a through hole formed at one side of the chamber so as to bring the fine liquid metal droplet, whose shape is to be changed in the chamber, into contact or non-contact with the signal transmission line; an operating member disposed on the second layer member, and provided at an open side of the chamber so as to provide deformability to the fine liquid metal droplet through the open side of the chamber; and a third layer member for defining the position of the operating member, and coupled to the first layer member and the second layer member.