The utility model discloses an oversized-area stainless steel suspended ceiling deformation prevention structure. The structure comprises convex surface stainless steels I (1), concave surface stainless steels II (2) and a steel skeleton basic layer (3); the steel skeleton basic layer (3) is mounted on a lower layer of a suspended ceiling to be used as a skeleton basic layer of the suspended ceiling; the convex surface stainless steels I (1) are fixed below the steel skeleton basic layer (3) at intervals; the concave surface stainless steels II (2) are detachably mounted among the convex surface stainless steels I (1) in a layering and overlapping way to form unit modules; the unit modules are mutually lapped to form the whole suspended ceiling structure. According to the oversized-area stainless steel suspended ceiling deformation prevention structure, the technical problems that the flatness and the deformation of the oversized-area stainless steel suspended ceiling are not easily controlled and the field point location is not easily drilled are effectively solved, the quality risk is reduced, the decoration effect of the oversized-area stainless steel suspended ceiling is enhanced, the construction efficiency is improved, the manpower installation cost is reduced, and the productization level of the stainless steel suspended ceiling is promoted.