Puccinellia tenuiflora is a monocotyledonous halophyte species belonging to the Gramineae. It has strong ability for surviving in the extreme saline-alkali soil (pH range of 9-10). In the present study, proteins from leaves under various Na2CO3 treatments were separated and visualized on Coomassie Brilliant Blue-stained two-dimensional gel electrophoresis (2-DE) gels. After gel image analysis on the base of the calculated average vol% values of each protein spot, 174 protein spots were detected as abundance changed protein spots (1.5-fold changes, p < 0.05). Among them, 104 protein spots were identified using MALDI-TOF MS/MS and Mascot database searching. Thus the 104 protein identities represented 80 unique proteins were taken as Na2CO3-responsive proteins in leaves. After integrative analysis by BLAST alignment, Kyoto Encyclopedia of Genes and Genomes, and referring information from related literature, they were classified into 10 functional categories, including photosynthesis, carbohydrate and energy metabolism, other metabolisms, stress and defense, membrane and transport, signaling, protein synthesis, folding, and turnover, cell wall mechanism, cell cycle, and miscellaneous or unknown.