The invention discloses a floor slab concrete construction method applying a floor slab trolley. The applied floor slab trolley is formed by a floor slab trolley unit or longitudinally splicing a plurality of floor slab trolley units, and each floor slab trolley unit comprises a trolley moving and fixing system and a steel template connecting and positioning system. The method sequentially includes the steps: laying traveling rails, moving and enabling the trolley to be in place, adjusting first hydraulic jacks and bearing jack, adjusting second hydraulic jacks, adjusting third hydraulic jacks, mounting screw rod jacks, mounting lateral screw rod jacks or oppositely-supporting steel rods, mounting a mouth closing net and a waterstop steel plate, pouring concrete, removing a formwork and the like, and needlessness or reduction of setting-up of a steel pipe support and a splicing template is realized. By the method, three-orientation accurate adjusting can be realized, and high mounting and demounting speed and low worker labor intensity are realized; construction process of the floor slab trolley can be accelerated by adopting early formwork removing technology, so that construction period is shortened, construction cost is saved, and quickness, stability and reliability in construction are realized.