The diluted magnetic semiconductor Ga1−xMnxN was achievedby low-pressure metal organic vapour-phase epitaxy (LP-MOVPE).Proton-induced x-ray emission was employed non-destructively, quicklyand accurately to determine the Mn-doped content. The magnetic propertywas measured by a superconducting-quantum-interference-device (SQID)magnetometer. Apparent ferromagnetic hysteresis loops measured at orabove room temperature are presented. No ferromagnetic secondary phaseswere detected by high-resolution x-ray diffraction. The experimentalresults show that the ferromagnetic signal firstly decreases and thenincreases with the increasing Mn-doped content from 0.23% to 4.69%and it is the weakest when Mn content is 0.51%. The annealingtreatment could make the ferromagnetic property stronger.