Two different ways are adopted for pretreatment of squid, one is salted first, then vinegar treated and the second vinegar first then salted. High barrier composite membrane is used in packaging processing. The effects on squid’s freshness are tested by examining different concentration of salt solution, different pH value, different soaking time, different packaging films and different pretreatment methods. The result shows the best preservation could be achieved under the condition of salt/water volume friction of 3%, vinegar solution pH=4, with vinegar first and salted for 30min, with PE/PA composite membrane packaging.