Objective To explore the application of objective audiological examination in the diagnosis of occupational noise deafness by multi-frequency steady-state evoked potential (MSEP) in order to differentiate and diagnose occupational noise deafness. Methods Multi-frequency steady-state evoked potentials and pure tones were measured at four frequencies (0.5k Hz, 1k Hz, 2k Hz,4k Hz) in 61 objective deafness, 64 exaggerated deafness and 35 cases of normal hearing. The results were analyzed by variance analysis, pearson correlation analysis and linear regression analysis. Results The correlation coefficients of response thresholds of MSEP and pure tone test thresholds were 0.66, 0.85, 0.80 and 0.73 in normal hearing group, 0.83, 0.84, 0.90 and 0.78 in objective deafness group, and 0.38, 0.35, 0.50 and 0.48 in exaggerated deafness group, respectively. This indicated that MSEP could be used as objective hearing test to identify pseudo deafness or exaggerated deafness. Conclusion Differential diagnosis of occupational noise deafness by MSEP is feasible and has clinical application value.