The invention relates to a three-frequency frequency reconfigurable antenna for coplanar waveguide feed, which comprises a metal microstrip on the upper layer, a dielectric substrate on the middle layer and a back floor board on the lower layer. The metal microstrip comprises a radiating patch, a coplanar waveguide floor board, a coplanar waveguide feeder, a matching branch and four PIN (P-Intrinsic-N) diodes, and the radiating patch is surrounded by the coplanar waveguide floor board. The coplanar waveguide floor board is connected with the radiating patch through the four PIN diodes, the coplanar waveguide feeder is arranged at a central opening on the lower edge of the coplanar waveguide floor board and is connected with the radiating patch into a whole, and the matching branch is connected with the upper part of the coplanar waveguide floor board into a whole. The back floor board is arranged on the back of the dielectric substrate and corresponds to metal coatings on the lower part of the coplanar waveguide floor board and under the coplanar waveguide feeder, and a microstrip antenna is formed by the back floor board and the metal microstrip. The three-frequency frequency reconfigurable antenna can work on three wireless communication frequency bands of 0.9GHz, 1.8GHz and 2.4GHz. Moreover, directional diagrams on the three frequency bands basically remain unchanged and have larger bandwidth. Meanwhile, the design of a switch bias circuit can be eliminated, and the impact of a switch on the radiation performance of the antenna can be reduced.