the invention relates to an electronic component with sn rich deposit layer on the part for electric connection , wherein the sn rich deposit layer is a fine grained sn rich deposit layer composed of grains with smaller size in the direction perpendicular to the deposit surface than in the direction parallel to the deposit surface . it also relates to a process for plating an electronic component , so as to form a sn rich deposit layer on the part for electric connection , comprising the steps of : adjusting the composition of tin plating solution in which starter additive and brighter additive are included ; moving the electronic component through the tin plating solution , so as to form a fine grained sn rich deposit layer on the part for electric connection . as compared with the prior art , the invention can validly inhibit the whisker growth with low cost and reliable property .