The effects of exogenous antibiotics on the physical and chemical parameters of cow dung anaerobic fermentation was studied, with cow dung and straw as raw materials during sequencing batch anaerobic fermentation.Meanwhile, the degradation rates of three antibiotics in anaerobic fermentation were explored. The results showed that the addition of the three antibiotics of 10, 30, 60, 120, 240 mg/L had different effects on the methane yield, pH,ORP and conductivity. Ciprofloxacin had the strongest effect on the inhibition of methane, followed by norfloxacin,enrofloxacin is the least obvious. The higher the concentration of antibiotics, the stronger the inhibition of cumulative gas production. For example, after adding 10 mg/L enrofloxacin, the methane production decreased by 51%;when adding 240 mg/L ciprofloxacin, its production was reduced by 90%. In the process of anaerobic fermentation,the three antibiotics were also gradually degraded. For example, with the addition of 10 mg/L enrofloxacin, norfloxacin and ciprofloxacin, their degradation rates were 75.39%, 56.40% and 44.45%, respectively in 50 days.