The stirred bioreactor is widely used in cell culture in the biopharmaceutical industry, but there is a lack of research on optimization of agitator blade in bioreactor based on the standard of agitator blade and the actual demand. Aiming at the problems that the design parameters interval in the agitator blade standard is large, the parameters of the bioreactor stirring paddle design are difficult to determine, and the shear force and power consumption lack reference in the design of the agitator blade. The agitator blade of the 200 L bioreactor was preliminarily optimized based on the orthogonal method and CFD, and the effects of different agitator blade diameters, agitator blade width, distance from agitator blade center to bottom, and rotational speed on agitator blade shear rate and agitation power of the tri-oblique blade were obtained by using the method of range analysis. Combined with the velocity dead zone distribution, streamline distribution, and shear force distribution, a design scheme that ensured the effect of cell culture was selected. This scheme was conducive to fluid circulation and could promote the mixing of culture medium and gas-liquid mass transfer. At the same time, the fluid needed sufficient kinetic energy and overall flow velocity. According to the orthogonal optimization scheme, the multi-objective optimization variables interval was determined, and the shear force and power consumption were taken as the optimization objectives. Based on the Kriging model and multi-objective genetic algorithm, the design variables interval of the tri-oblique blade propeller that is beneficial to cell culture was proposed. The optimal parameter combination of the agitator blade with average shear force of 0.789 Pa and power consumption of 0.395 W was obtained, which provided a method and data reference for the design and optimization of the bioreactor under different actual needs.