The invention provides a novel ribbed heavy plate design method. Plate bottom rebars on the ribbed beam joints of a heavy plate are densified. Through the method, the stress performance of ribbed beams can be remarkably improved, mainly, the ultimate bearing capacity of the structural heavy plate is remarkably improved, the stress of rebars of a floor top plate close to the ribbed beams is reduced, the stress concentration phenomenon is relieved, and the maximum tension strain of the rebars develops towards the middle area of the floor top plate.