The effect of cataract surgery is affected by various factors, such as the measurement of preoperative biological parameters, the formula for calculating refractive force of intraocular lens(IOL), surgical methods and surgical techniques. The axial length(AL)is an important parameter for calculating the refractive force of IOL. At present, the main methods of measuring AL are ultrasonic biometry and optical biometry, and these two methods have their own advantages and disadvantages and complement each other. The calculation formula of refractive force of IOL has been continuously updated in the past decades. In recent years, many new calculation formulas have appeared, such as the Barrett Universal Ⅱ formula(BUⅡ), the Kane formula, the Olsen formula, the Hill-radial basis function(Hill-RBF)formula, etc. This paper mainly summarizes the advantages and disadvantages of the two AL measurements, and compares the accuracy of the IOL refractive force calculation formula at different AL.