The invention discloses a variable lane control method based on vehicle-road coordination, which comprises intersection signal control equipment, a vehicle-road coordination device is loaded in the intersection signal control equipment, and the vehicle-road coordination device loads communication and perception capabilities for a signal control machine by integrating a roadside communication device in the signal control equipment and integrating a vehicle-mounted device in a vehicle. According to the technical scheme, the method is characterized in that a specific implementation mode is as follows: a left-turn phase and a straight-going phase, the left-turn phase: L1-L2 is greater than 4, it is confirmed that a left-turn queue is relatively long, L2 is recorded, and a next acquisition period is entered; L1-L2 is less than or equal to 4, and the default mode of the variable lane is straight; when the straight-going phase L1-L2 is larger than 4, it is confirmed that the straight-going queue is long, and the default mode of the variable lane is straight going; L1-L2 < = 4, it is confirmed that the left turn queue is long, L2 is recorded, the next acquisition period is entered, and ifthe conditions 1 and 4 occur in the two acquisition periods and L2 is greater than a set threshold value, the variable lane is changed.