The invention discloses a mould for bidirectional adjustable rail supporting groove without bumping shoulder, which belongs to the technology field of the rail supporting groove on the bottom template of the bearing platform type frame rail board mold. The invention comprises a rail supporting groove core and a rail supporting groove frame connected to the outside of the rail supporting groove core, the internal shape of the rail supporting groove core matches with the shape of a bearing platform without bumping shoulder, the rail supporting groove core is provided with a pair of mounting holes corresponding to a pre-buried sleeve on the bearing platform without bumping shoulder, a side plate of the rail supporting groove frame is connected with a longitudinal adjusting mechanism, and the bottom of the rail supporting groove core is connected with a height adjusting mechanism. The invention can adjust the rail supporting groove frame, in order to meet the requirements that a transition curve type rail plate requires the bearing platform thereon to adjust position according to the curve of the path; the invention is particularly applicable to preparing the rail plate of the transition curve section of the high-speed rail.