The invention discloses a building height optimization design method based on a simulated annealing algorithm, aims to provide a method for solving a combination optimization problem by the simulated annealing algorithm, and a program design thought, and is applied to practical building planning optimization design. The building height optimization design method comprises the following steps: firstly, evenly dividing a proposed building area into a plurality of grids, upwards stretching the grids to form small columns, carrying out sunlight analysis on a window on the basis of a position relationship of the small columns and the blocked window, and determining the sunlight cumulative time of the window; then, on the basis of the minimum sunlight time constraint of the window, constructing a mathematical model of the optimal height of the proposed building; and finally, aiming at the mathematical model to design and solve the steps of the simulated annealing algorithm. The building height optimization design method aims at a specific mathematical model to design the reasonable simulated annealing algorithm. Compared with a traditional manual way, the automatic analysis calculation of software is quick, accurate and efficient, and an effective method and approach is provided for realizing the design of saving type land.