This invention relates to a microstrip array antenna, especially a broad-band dual-polarized microstrip array antenna having parallel feeding structure whose consist of two parts power supplying layers each of which generates its own polarization respectively. And the broad-band dual-polarized microstrip array antenna according to the present invention arranges transmission paths for two separate linear polarization on a different layer each other in order to minimize an interference effect and a proximity feeding method and an aperture coupled method are used in order to get two separate polarization.