Abstract: To study the application of microorganisms in the field of gutter oil's identification. It used gutter oil refining technology to refine gutter oil. Eight strains of fungus were isolated from gutter oil, which showed that the strain DGY03 in gutter oil medium grew quickly, and it used the methods of morphological observation and molecular biology to identify it. It had studied its feasibility in the field of gutter oil's identify at the same time. The growth rate of and colony growth of the strain DGY03 in gutter oil and four kinds of edible oil medium were observed and compared. The results showed that the strain of colony morphology and microstructure were basically the same as Aspergillus, and the ITS sequence showed 100% homogeneous to Aspergillus tubingensis. So the strain DGY03 was determined to be Aspergillus tubingensis(The Genbank accession number:MF186869). And the growth rate and colony growth of strain DGY03 were significantly better than that of the other four edible oil media. The growth rate of the strain DGY03 on the gutter oil medium was 0.64cm/d, and the growth rate of soybean oil, rapeseed oil, corn oil and peanut oil medium were 0.21, 0.28, 0.24, 0.29 cm/d. Thus it could preliminary inference that it was feasible to use the strain DGY03 as indicator bacteria to identify gutter oil.