For tissue engineering, pore structure is an essential element in the development of scaffolds. In this paper, we obtained highly porous cross-linked partially hydrolyzed poly (vinyl alcohol) (PVA) hydrogels by templating concentrated CO2-in-water (C/W) emulsions, which avoid the use of traditional organic solvents and additional surfactants. This method is very convenient for the formation of biocompatible PVA hydrogels, because redundant crosslinking agent and catalyst could be easily removed by washing with the absence of organic solvent and surfactants, and would have widespread applications due to the biocompatibility of the resulting materials. These PVA hydrogels were further evaluated for cellular growth and proliferation to demonstrate their applications in tissue engineering. (C) 2015 Elsevier Ltd. All rights reserved.