In order to investigate the adverse effects of salt on microbial flora, a study of anaerobic treatment of monosodium l-glutamate fermentation wastewater with high calcium chloride concentration and high COD concentration was carried out using a laboratoryscale UASB reactor. An anaerobic sludge culture obtained from a beer brewage plant was used as the seed. The results indicated that: without acclimation, there was no evident inhibition performance when the chloride ion concentration was under 4500mg/L, while inhibition level obtained at a chloride ion concentration of 5000mg/L. However, a preferable COD removal rate could be achieved after acclimation, and the chloride ion inhibition level exceeded to 25,000 mg/L (3% CaCl2). When the salt concentration level was between 1 and 3% (CaCl2), the average COD removal rate could be above 80% at around 5000 mg/L COD initial concentration and 24 h hydraulic retention time.