Abstract: The LLDPE/LDPE ( 3 ∶ 1) material as a substrate and MIT ( 2- methyl- 4- isothiazolin- 3- ketone) as an organic anti- mildew filler were combined to improve mildew proof PE films. The film with thickness of 0.016 ~ 0.017mm, ash content of 0.20% to 0.24%, MIT concentration of 0.10%, 0.15%, 0.20%, 0.25% and 0.30% ( w /w) was prepared.Results indicated that all samples with MIT reached the level 1 based on the QB /T2591-2003.Compared with control films, samples with 0.30% MIT had an 36.23% decreasing in elongation break rate and lower transparency.With the increase of MIT amount, the tensile strength and heat sealing of samples were reinforced significantly.And the tensile strength and heat sealing of 0.30% MIT was higher than the blank films 18.41% and 54.65%, respectively.After packaged with samples at 8℃ for 12 days, the etiolated rate and decay rate of the rapes decreased with the increasing of MIT amount.The etiolated rate and decay rate rape packaged with 0.30% MIT/PE ( 7.3% and 0.56%) were markedly lower than the packaged with controls ( 13.2% and 1.36%) 44.70% and 58.82%, respectively.