Abstract: The equivalent parameter models for series and parallel feed microstrip arrays are respectively built, according to the array’ structure. Then the limitation of the microstrip feed network’s power loss on the gain of microstrip antenna array is analyzed quantificationally. With the help of the low loss hybrid feed network which is composed of microstrip lines and coaxial cables, a C-band 4×24 elements microstrip antenna array with high efficiency is designed based on the series-parallel feed architecture. The measurements of the array are better than design goals, especially that the gain of the array reaches 25.4 dB, 1.1 dB higher than that of the series array of the same element number, and the radiant efficiency is 64.5%. The measurements are in good accordance with the theoretical