Abstract: Based on the NanShan 25m Radio Telescope of XAO (Xinjiang Astronomical Observatory), we design a 4 × 4 rectangular microstrip antenna array as feed array with element spacing of 0.7 times wavelength. A 2 × 2 sub-array synthesizes a single beam, capable of off-axis scanning up to one beamwidth. It can instantly form 9 beams. After fabricating the array prototype in the laboratory, we test that the return loss of each port in the array is below -10dB, and the coupling between the different array elements is below -30dB. The beam gains of the independent array element and after uniform weighting of 2 × 2 sub array and 4 × 4 full array are 3.64, 14.7, and 18.5dBi, respectively. By selecting the corresponding array elements under different scanning methods and using the conjugate matching method for weighting, and importing the measured results of the feed array into the simulation software to simulate various performance under a 25m reflector, the final antenna gain is around 30dBi, the sidelobe level is below -20dB, the beam width of the axial beam is 0.61 degrees, and the beam scanning angle is 1.6 degrees. Although there are slight differences between the above measured data and simulation results, which are related to array fabricating, amplitude and phase adjustment, and testing platform accuracy, the relevant work has accumulated experience for the design and measurement of feed array for phased array receiver, and has good guiding significance for future array design and performance verification with more array elements.