A stable porous superhydrophobic high-density polyethylene (HDPE) surface with water contact angle of 160.0 +/- 1.9 degrees and sliding angle of 2.0 +/- 1.6 degrees was obtained by adding ethanol in humid atmosphere at 5 degrees C. Soaked in water with temperatures ranging from 5 to 50 degrees C for 15 days, even suffering compressive forces, and the water contact angles were still higher than 150 degrees. After water flowed through the Surface continuously for 30 min, even water droplets with a diameter of 4 mm dropped onto the HDPE surface from 30 cm high for 10 min, the water contact angles were also higher than 150 degrees. A brief explanation to the formation of the porous superhydrophobic HDPE surface was put forward. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 1626-1632, 2009