Surface morphology of polychloroprene (CR) and piperylene–styrene copolymer (PSC) blend films was investigated by atomic force microscopy. The dependence of the blend films surface roughness on PSC content was studied with both fractal and correlation analyses. Gaussian profiles for the height distribution upon blend composition were observed. The topographical images of CR/PSC blends have been characterized by root‐mean‐square roughness, lateral parameter, and fractal dimension values. The analysis showed that quantitative description of surface roughness leads to the differentiation components of polymers blends. Lateral parameter and fractal dimension values of CR films were similar to those of CR/PSC 60/40 wt% blend films. This effect is associated with CR enrichment at the blend film surface. POLYM. ENG. SCI., 47:824–829, 2007. © 2007 Society of Plastics Engineers