The invention provides a microbial fertilizer for improving saline alkali soil. The microbial fertilizer comprises the following raw materials in parts by weight: 45-55 parts of turf, 25-35 parts of Angel yeast residues, 5-15 parts of monoammonium phosphate, 5-15 parts of ammonium sulfate and 1-3 parts of a complex microbial inoculant. According to the microbial fertilizer provided by the invention, the microbial flora is in mutual promotion with organic matters and inorganic matters, the components supplement one another, the effective living bacteria count is not less than 50million per gram, the content of the organic matters is not less than 55 percent, the total nutrient is not less than 11 percent, the content of ammonium nitrogen is not less than 4 percent, the content of P2O5 is not less than 4 percent, the content of K2O is not less than 3 percent, and the pH value is 5.5-6.0. Under the co-actions of the components, the effects of rapidly reducing the soil salinity and alkalinity and increasing the content of organic matters, available phosphorus and ammonium nitrogen are achieved, and the conditions that the granular structure of the soil is poor, the soil permeability is reduced and the activity of the microbial flora is inhibited are improved.