Shrinkage properties of drawn textured Poly(trimethylene terephthalate, PTT) yarn, which has been developed recently, were investigated to provide fundamental information for the textile industry. Shrinkage ratio characteristics on PTT yarn with six different count were investigated with tension, dry and wet thermal temperature. In non-tension, the shrinkage ratio were increased to increasing temperature at dry and wet thermal treatment, and in tension, the shrinkage ratio were increased to increasing tension at dry and wet thermal treatment.