In order to improve the preparation quality of monolayer (ML) tungsten selenide (WSe₂). We improve the traditional chemical vapor deposition (CVD) method. ML WSe2 film is prepared by introducing a trolley to construct a growth method that can regulate the deposition area, precisely control the growth time, and achieve rapid temperature reduction. Optical microscope and atomic force microscope are used to characterize the size, fluorescence intensity and morphology of the prepared materials, which proved that a high-quality ML WSe2 film is successfully prepared by the push-pull trolley method. The large-area, high-quality, single-layer WSe₂ film can be stably prepared by the trolley based method, which provides an important basis for its future application in the information, energy, and biology frontier fields.