Vacuum packaging is widely used in the food industry. Because of the gas in the vacuum packaging are fully withdrawned, vacuum bag maintained in a highly reduced pressure state. Microorganisms could hardly survive in such low-oxygen conditions, so food in vacuum pouch could keep fresh. Low-oxygen conditions could also keep food from oxidation. As we known, the unsaturated fattyacid in food could be oxidized easily which will ruin the flavour, make the tastes be worse, cause food to be bad. What's worse, oxygen coule destory vitamin A and vitamin C, make the food color get dim. In order to keep food be fresh, nutrient and beautiful, more and more manufacuturers choose to use this new kinds of package. Generally vacuum bag play a inportant role in packaging of the salt baked foods, pickles, soy products, meat products, convenience foods, canned soft food and so on.