This study compares the parameters and the performances of conventional microstrip antenna and the antenna with cells of CSRR designed by using CST Microwave Studio software. Both of them are constructed with the same specifications and operated at frequency of 3.5 GHz. Based on the simulation results obtained, the microstrip antenna with cell of CSRR metamaterial provide better parameters and performances than the conventional microstrip antenna in terms of return loss, VSWR, gain, bandwidth, impedance reference, directivity, and radiation pattern. It indicates that the presence of cells of CSRR metamaterial on antenna could improve performances and miniaturize antenna dimensions with size of 49.44% smaller than conventional microstrip antenna. It is expected to be able to apply to the WiMAX. The designed antenna has met standards or matching for being fabricated.