Gellan gum,a kind of microbial polysaccharide with great property of forming gel,can be widely used in food,pharmaceutical and other industries.However,the high cost limits its widespread applications.In this study,corn steep liquor and urea were used as cheap nitrogen sources for the fermentation of gellan gum,and initial glucose concentration,aeration and agitation were optimized to develop a new process with cost advantage.The results showed that the optimal initial glucose concentration and aeration for gellan gum fermentation were 40 g/L and 1vvm,and the optimal agitation control strategy was 400 r/min for lag phase(0-12 h),800 r/min for exponential phase(12-32 h),and 400 r/min for stationary phase(32-40 h).Under these conditions,the yield,weight-average and viscosity of gellan gum were 16.7 g/L,625.8 kDa and 7.495 Pa·s,respectively.