Abstract: Based on a short retrospect of the developmental history of light scattering theory, the problems in conventional Mie scattering calculations are analyzed. A simple yet accurate algorithm for the improved Mie scattering calculations is described in detail. A new data type named“EDecimal” is defined, and its basic mathematical operation and trigonometric functions are developed. The dynamic chain is used in implementing the efficient C++ code for fast and accurate Mie calculation.The code can handle extreme cases in Mie scattering calculations and reduce the time complexity of this algorithm. By comparison with Wiscombe's MIEV0 code requiring a same precision,this method shows up its the accuracy and reliability.