Abstract: The genotoxicity of Aspergillus niger mutants induced by electron beam irradiation was evaluated by Ames tests, micronucleus tests of mouse bone marrow cells and mouse sperm abnormality tests. The results showed that in the Ames test, the number of returned colonies in each dose group of Aspergillus niger did not exceed 2 times of the number of spontaneous colonies with or without addition of S9 metabolic activation system, indicating that A. niger mutants did not cause chromosomal abnormalities Mutation effect. Micronucleus test in mouse bone marrow cells, a significant increase in mammalian polychromatic erythrocytes micronucleus cells (p>0.05), could not be caused by Aspergillus niger mutants, Aspergillus niger mutants could not cause significant damage on cell chromosome, indicating that Aspergillus niger mutant had no mutagenic effect. In the mouse sperm deformity test, the sperm deformity rate of each dose group of Aspergillus niger had no significant difference compared with the solvent control group (p>0.05), which indicated that A. niger mutants did not cause teratogenic effects on the sperm of mice effect. Therefore, under the experimental conditions, Ames test, mouse bone marrow micronucleus test, mouse sperm abnormality test results were negative. Aspergillus niger electron beam irradiation mutants belonged to the actual non-toxic level, which had no genotoxic effect.