In order to overcome the issues of clock synchronization required in time division multiplexing (TDM) technology and the inflexibility of frequency division multiplexing (FDM) systems, an accurate visible light localization algorithm based on code division multiplexing is proposed. The algorithm realized symbol synchronization in asynchronous conditions and performs visible light positioning. The Simulation results show that when covering more than 80% of the area of a room, the average positioning error of the algorithm is 6.9cm, and the maximum positioning error is about 11cm, which is suitable for most indoor location-based services. In addition, the relationship between the positioning accuracy of the system and the field of view of the receiver and the height of the receiver above the ground is analyzed. It is found that in a certain range, the larger the field of view of the receiver, the poorer the positioning performance of the system; while the larger the height of the receiver above the ground, the better the positioning performance of the system.