High effect flocculant compound bacteria were screened out with the product bacteria of flocculant in soil. Their system appraising study shows that two were actionomyces and the other was microzyme among the three bacteria. According to nSrDNA, the three bacteria were marked at a molecule level and the system growth tree was established,ensuring the position of compound bacteria at the molecule level. The purificant which was made of the compound bacteria has spreading value because of its excellent clearing effect for organic and inorganic polluted water.