A straddle type track beam support with a line ultrahigh function comprises an upper base plate, a middle base plate, a lower base plate, at least one stepless height adjusting structure, a bottom plate, an ultrahigh plate and anti-pulling structures arranged at the two ends of the upper base plate and the lower base plate, wherein the upper base plate, the middle base plate, the lower base plate,the at least one stepless height adjusting structure, the bottom plate and the ultrahigh plate are arranged from top to bottom; the lower surface of the upper base plate and the upper surface of themiddle base plate are planes which are in sliding fit, the upper surface of the middle base plate and the upper surface of the lower base plate are arc surfaces which are in longitudinal rotation fit,the lower base plate is arranged on the bottom plate through the stepless height adjusting structure, the bottom plate is fixedly arranged on the ultrahigh plate, the lower surface of the bottom plate is a transverse column surface, and the upper surface of the ultrahigh plate is provided with a transverse column surface matched with the lower surface of the bottom plate. The low-friction sliding, stepless height adjusting, line ultrahigh and replaceable functions of the support are achieved, the safety and reliability of stress of a support structure and the convenience of construction and maintenance can be effectively improved, and the requirements of a straddle type monorail transit track beam for support safety running and construction convenience are met.