Two biomimetic superhydrophobic polymeric surfaces were obtained by a simple approach under ambient atmosphere. Water and ethanol were used as the nonsolvents in the method of phase separation in different systems. The influences of various factors in the process were investigated. Both of the as-prepared films showed excellent superhydrophobicity, depending on the high contact angle and the low contact angle hysteresis. Moreover, the classic and a new modified Cassie-Baxter relation were used on the polystyrene and poly-alpha-methyl styrene films to confirm the superhydrophobic performance. (c) 2010 Elsevier B.V. All rights reserved.