A sintered copper alloy material product is provided on which a skin (particularly, a skin of a solid lubricant with low adhesion, such as PTFE or molybdenum disulfide) is securely formed on the surface thereof and has good sliding properties and good seizure resistance under unlubricating environments or under corrosive environments. A sintered copper alloy material is processed using a selective chemical etching solution containing a compound of one kind or more selected from the group of consisting of peroxide, peroxocompound, chromic acid and permanganic acid and a compound of one kind or more selected from the group of consisting of phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, zirconic hydrofluoric acid, titanic hydrofluoric acid, titanic acid, molybdic acid, tungstic acid, vanadic acid, niobic acid, and organic chelating agent. Thereafter, a lubricating skin is on the surface of the processed material.