The work aims to analyzethe effect of spontaneous air-conditioned blend films PLLA/ PLLA-PEG-PLLA (PLGL) on storage quality of postharvest snow peas and obtain the appropriate air permeability ratio to extend the fresh-keeping period of snow peas. The snow peas from the market were taken as testing materials. The five types of films including PLLA / PLGL10, PLLA / PLGL20, PLLA / PLGL30, PLLA, and PE were used to pack the snow peas to observe the changes of gas, color difference values, chlorophyll content, malondialdehyde content, and weight loss rate during 24 days of the storage of peas at (4±1)℃. The results showed that the film made of PLLA / PLGL 30 was the most suitable package for fresh-keeping peas which showed good mechanical properties. The elongation at break was as high as 175.3%. And it improved the selective permeability ratio of O2 and CO2 from 2.9 to 6.1. At the 24th day of storage, the concentration in the bag consisted of 2.8% O2 and 5% CO2, which effectively delayed the decline of chlorophyll content and weight loss rate, reduced the accumulation of malondialdehyde, and extended the storage period of snow peas. The blended film processing is more environmentally friendly than PLLA film and PE film on the market, and possesses better preservation effect on snow peas.