The utility model provides a trestle cantilever beam with a cable placing groove, and relates to the field of building construction. The trestle cantilever beam with the cable placement groove comprises a plurality of cantilever beam bodies which are arranged side by side. Cable placing sections are arranged at the two ends of each cantilever beam body, and through cable placing grooves are formedin the length directions of the cable placing sections. The plurality of cable placing sections at the same end are detachably connected in sequence, and the cable placing grooves of the plurality ofcable placing sections are communicated. The trestle solves the technical problems that cables on an existing trestle are simple and messy in arrangement, constructors are prone to walking, materialsare inconvenient to transport, and potential safety hazards are prone to being caused.