The invention provides an optical path tracking calculation method and system. The optical path tracking calculation method comprises the steps that parameter values of measured laser are collected; based on the collected parameter values, a pre-constructed light parameter equation is solved by using a high-precision calculation method, and the laser propagation time is calculated; and calculatingthe track point of the laser based on the laser propagation time. According to the technical scheme provided by the invention, the light parameter equation is solved by adopting a high-precision calculation method according to a floating point stability calculation theory, so that the light path tracking accuracy is improved.