A construction method for a cantilever beam on a central pier. A scaled model of the cantilever beam on the central pier is established and tested to obtain the stress distribution regularities of the cantilever beam according to test data and analysis results of the scaled model, so as to find out week parts of the cantilever beam, and thus the optimization design can be performed to make the cantilever beam reasonably carry the load and improve the materials with a higher utilization ratio. The wheeled stand support used in the present application has a high turnover rate and it is easy and convenient to dismantle and assemble the wheeled stand support. A height of the cantilever beam mold can be adjusted by a hydraulic cylinder.