Polyolefin films having incorporated therein a compound of the formula CH₃CH₂(CH₂CH₂)_aCH₂CH₂(OCH₂CH₂)_bOH, where a is 9 to 25 and b is 1 to 10, exhibit superior long lasting fog resistance. The polyolefin films are useful as packaging film for moist products and as a greenhouse film for agricultural applications.