The objection of this invention is to provide an article with a foamed surface having a porous structure in the surface of a plastic base, an implant and a method of producing them. The article has a body and a superficial layer formed in a surface of the body, the layer including small-diameter and large-diameter pores, wherein part of the small-diameter and large-diameter pores are open pores which are open at the surface of the layer; the open pores have small open pores with an average diameter of 5 μm or less and large open pores with an average diameter from 10 to 200 μm; and the large open pores have an inner wall with passages connected with the small-diameter large-diameter pores. The implant is the article itself or the article with a bioactive substance in the layer thereof. The method provides an example of producing the article and implant.