The invention relates to a nuclear facility stainless steel covering structure. The nuclear facility stainless steel covering structure comprises a bottom layer (4) and a stainless steel surface layer (1) which is arranged above the bottom layer (4); an interlayer supporting part (3) and an interlayer connecting part (2) are arranged between the bottom layer (4) and the stainless steel surface layer (1), wherein the interlayer supporting part (3) is connected with the bottom layer (4) and the interlayer connecting part (2) is connected with the bottom layer (4) and the stainless steel surface layer (1); the nuclear facility stainless steel covering structure is on the basis of concrete (10) and the bottom layer (4) is connected with the concrete (10) for rooting anchoring. The invention also provides a construction process of the nuclear facility stainless steel covering structure. The nuclear facility stainless steel covering structure which is of a double-layer structure formed by the bottom layer and the stainless steel surface layer to form a drainage channel and a maintenance channel and accordingly the in-service monitoring, inspection and maintenance on the nuclear facility stainless steel covering structure is convenient, the installation cleanliness of the stainless steel surface layer during construction can be ensured, the stress corrosion produced on the stainless steel surface layer is avoided, the construction conditions can be simplified, and the construction period can be shortened.