Both air/He and air/O 2/He atmospheric plasma treatments are applied to desize PVA on cotton, then PDR (percent desizing ratio) and tensile strengths of cotton fabrics and single yams are measured. XPS and SEM are used to analyze the effects of atmospheric pressure plasma treatments on PVA. These treatments can both remove some PVA sizing and significantly improve PDR by washing, especially by cold water washing. The tensile strengths of cotton fabrics treated with atmospheric pressure plasma are the same as for the unsized fabric. XPS analysis of the plasma treated PVA films reveals surface chemical changes such as chain scission and formation of polar groups, which promote the solubility of PVA in cold water. Air/O2/He plasma is more effective than air/He plasma on PVA desizing.