Auxiliary tool for mounting cantilever beam without jig frame

The utility model discloses a jig-frame-free auxiliary tool for mounting a cantilever beam. The jig-frame-free auxiliary tool comprises a first fixing assembly, a second fixing assembly, a third fixing assembly, a fourth fixing assembly and a tension rod, the first fixing assembly is fixedly installed on a main body structure, the second fixing assembly is fixedly installed at one end of a cantilever beam to be installed, the third fixing assembly is fixedly installed at the other end of the cantilever beam to be installed, and the fourth fixing assembly is fixedly installed on a cantilever beam support of the main body structure. The third fixing assembly is connected with the fourth fixing assembly; the first fixing assembly is connected with the second fixing assembly through the tensioning rod. The cantilever beam is fixed through the four fixing assemblies, after the cantilever beam is installed, the fixing assemblies can be dismantled, the fixing assemblies are of a structure convenient to install and d