PROBLEM TO BE SOLVED: To provide a product in which a lead-free tinning film or a lead-free tin alloy plating film is formed, and which can be produced relatively easily without need of a complicated process while the generation of whiskers is suppressed over a long period. SOLUTION: The tin based plating film in which the growth of whiskers is suppressed is composed of a plating film with a double layer structure consisting of: a lower layer formed of a tinning film or a tin alloy plating film comprising ≤5 wt.% of at least one kind of metal selected from the group consisting of cobalt, copper, bismuth, silver and indium, and ≥95 wt.% tin; and an upper layer formed of a tinning film or a tin alloy plating film comprising ≤5 wt.% of at least one kind of metal selected from the group consisting of cobalt, copper, bismuth, silver and indium, and ≥95 wt.% tin. COPYRIGHT: (C)2006,JPO&NCIPI