This article presents a novel dual‐band orthogonally polarized square microstrip antenna for vehicle‐to‐nomadic devices communication system. The proposed antenna consists of a perpendicular feed for utilizing orthogonal linear polarizations and an H‐shaped slotted ground structure for obtaining dual‐band operation. Because of the geometrically axis‐symmetric H‐slot loading effect, the orthogonal polarization at each resonant frequency can be achieved. The measurement results of the proposed antenna have been successfully demonstrated in good agreement with the simulations of reflection coefficients, antenna gains, and radiation patterns. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:136–139, 2016