The invention provides a prestress T-beam tension method. The method comprises the following steps that 1, a beam end line is drawn, wherein a marked steel tape of 50 centimeters and a wall pulley areused, the steel tape and a wall pulley ruler are used for measuring the total length of a template, then the beam end line is measured and marked from the beam span center line to the beam ends, andfinally the beam end line is drawn according to mark points; 2, swallow tail strip clamping grooves are cut, wherein the swallow tail strip clamping grooves are cut at two beam ends by using oxygen-acetylene respectively, the clamping grooves are ground and finished by using a grinding machine after the clamping grooves are cut, and the interiors of the clamping grooves are flat and have no burr;3, swallow tail strips are mounted, wherein the swallow tail strips are cut on rubber strips, then the swallow tail strips are placed into the clamping grooves, the swallow tail strips are arranged onthe side back to the end mold and the beam end line, and the swallow tail strips are arranged firmly; 4, acceptance inspection is conducted. According to the prestress T-beam tension method, the situation can be effectively avoided that beam body concrete is in rigid contact with the bottom mold, so that stressed points are centralized on an embedded support plate, and accordingly the situation is avoided that concrete on the outer sides of the beam ends is directly stressed so that crack and blocking falling can be caused.