The invention relates to an accurate control method for a lateral bending problem of a large-specification and large-wall-thickness-difference multi-cavity aluminum profile material. The accurate control method includes the following steps that firstly, an aluminum bar is heated; secondly, an extrusion barrel is heated; thirdly, extrusion is carried out, specifically, the aluminum bar subjected toheat preservation is put into an extrusion machine to be extruded, the temperature of the extrusion barrel is kept at 420-440 DEG C, the temperature of the aluminum bar is kept at 490-510 DEG C, thetemperature of an extrusion mold is kept at 480-500 DEG C, and the extrusion speed is controlled to be 4+ / -0.5 m / min; fourthly, online quenching is carried out, specifically, two rows of spraying nozzles are arranged in the extrusion direction of the aluminum profile material, the length of the two rows of spraying nozzles in the extrusion direction of the aluminum profile material is 3 m, the water sprayed by the spraying nozzles is shaped like a 45 degree cone, the water spraying flow of the nozzles on the side, with larger wall thickness, of the aluminum profile material is controlled to be11.5-12.5 m3 / h, the water spraying flow of the nozzles on the side, with smaller wall thickness, of the aluminum profile material is controlled to be 7.5-8.5 m3 / h, the ratio of the water spraying flow of the thicker side to the water spraying flow of the thinner side is controlled to be 1.3-1.8; and fifthly, straightening is carried out, specifically, the straightening rate is 1-2%. The problem of lateral bending of the profile material can be solved.