Abstract: A new catalyst sodium nitrate(SN) used for cotton fabric durable press finishing with BTCA was developed,which is non-phosphorus and environment-friendly.With SN concentration of 4% in 6% BTCA finishing system for cotton fabric,desirable DP effect of cotton fabric could be obtained with 180 ℃/120 s curing condition.By means of chemical analysis and IR spectrum,the catalyzing mechanism of SN was suggested that as a nucleophilic reagent,SN reacts with carboxyl groups in BTCA,which is favorable for froming anhydride of BTCA from dehydration and consequent esterifying with cellulose.