The way to match the ratio of RGB trichromatic lights to get arbitrary color of light quickly and accurately is of great significance. An easily realizable RGBLEDs color matching model with simple structure was proposed. An arbitrary color can be matched by changing trichromatic LED radiation power in the way of current amplitude modulation, which in turn adjusts the proportion of each color′s luminous intensity. At the same time, an accuracy evaluation indicator for color matching model was given. Based on the model, a dichotomy algorithm of RGB color matching is employed so that the chromaticity coordinates of mixed color can be quickly matched to a specified scope. The simulation results prove the correctness and validity of the algorithm. This algorithm has a high value in practical application for its rapid convergence and high precision color matching.