Radar can be used for concrete inspection application to prevent structural failures. One of its components is the antenna. In this paper, a design of 1×4 microstrip array antenna integrated with unequal Wilkinson power divider using Dolph-Chebysev method on Epoxy FR-4 substrate with a dielectric constant of 4.3 was developed. Antenna is designed and simulated using CST software. The working frequency is in the ISM Band of 2.4-2.5 GHz with return loss -10 dB. The simulation results show that the array antenna operates at frequency 2.34-2.58 GHz or bandwidth of 243.6 MHz. In addition, the antenna has a gain of 4.39 dB, horizontal beamwidth of 27.8°, vertical beamwidth of 130.8°, front-to-back ratio of -21.87 dB, and sidelobe level of -13.2 dB. The measurement results show that the array antenna operates at frequency 2.35-2.59 GHz or bandwidth of 233 MHz. Moreover, the antenna has gain of 5.12 dB, horizontal beamwidth of 26°, vertical beamwidth 70°, front-to-back ratio of -20.22 dB, and sidelobe level of -17.45 dB.