In this article, we proposed a miniaturized 5-elements array GPS microstrip antenna for anti-jamming. For mounting on small air vehicles such as drones, the size of the proposed array antenna was set to 100 mm × 100 mm. To implement this, the radiating element was miniaturized through perturbation theory and high dielectric. For miniaturization of the radiating element, the size of the rectangular radiating element was reduced, and an extension line up to the size of the basic radiating element was formed in each of the four corners. It was folded in an “L” shape and lowered at a right angle to the radiation opening. When arranging, the antenna was rotated by 90 degrees and arrayed sequentially to arrange the feeding point at the corner, avoiding an influence on the interference. In addition, the centered antenna was designed with lowered height of the dielectric to minimize interference with the other four. The consequent single antenna resulted in the size of 19.7 mm × 19.3 mm, achieving 94.5% of miniaturization. This led average isolation between the corner and the center to be −17.59 dB or less. At the center frequency of 1.575 GHz, the average bandwidth for the five radiating elements was at 17.8 MHz. Additionally, the average gain of the E_θ component was −4.62 dBi in the yz-plane and − 3.58 dBi in the xz-plane, and efficiency value was 69% in simulation. As a miniaturized 5-elements array GPS microstrip antenna, it obtained sufficient bandwidth and succeeded to gain to location information in the GPS L₁ band.