Abstract: The polarographic behaviour of an azo-compound produced by the reaction of Methy amine phosphorus (MAP)-with 8-hy droxyquinoline(Oxin),in the ammonia medium has been studied.The yellow orangeazo compound grives a sensitive adsorption ware at the potential of -0.54V(VS.SCE) the height is directly proportional to concentration of MAP Over the range of 0.02～1.5μg/ml.The method is simple and selective whe applicd to water and air sampoles it gives almost the same results those the colorimetry.