Closely　connected　with　the　growing　importance　of　consumer　demand　for　safe,　non-toxic,　biodegradable　films　for　food,　this　study　developed　a　new　kind　of　nanocomposite　edible　film　with　poly-γ-glutamic　acid　(PGA)　and　chi-tosan　(CS)　as　raw　materials.　Due　to　the　ionic　interaction　to　form　homogeneous　polyelectrolyte　complex　between　PGA　and　CS,　the　hydrophilic　nature　of　PGA　can　be　better　controlled.　Methods:　to　get　the　optimum　CS　concentration,　the　influence　of　CS　concentration　on　film　characterizations,　including　water　content　(WC,　%),　total　soluble　mater　(TSM,　%),　transparency　(%),　color,　water　vapor　permeability　[WVP,　(g·mm)/(m2·d·kPa)],　moisture　sorption　isotherm　(MSI),　tensile　strength(TS,　MPa)　and　elongation　at　break　(EB,　%)　were　studied.　Result:　films　with　better　physical　mechanical　properties　were　made　when　CS:PGA　was　1:3,　with　WC　of　17.78±1.10%,　transparency　of　70.77±0.38%,　TSM　of　(42.85±1.05)%,　WVP　of　only　1.63±0.07g·mm/(m2·d·kPa),　TS　of　8.69±2.27,　EB%　of(46.24±5.37)%.　©,　2015,　Chinese　Institute　of　Food　Science　and　Technology.　All　right　reserved.