PURPOSE: To obtain a non-vinyl chloride plastisol which is storage stable at room temperature for a long period of time and has a high toughness and heat resistance.

CONSTITUTION: A plastisol is a copolymer of from 3 to 20 pts.wt. unsaturated carboxylic acid compound, from 0.2 to 10 pts.wt. ethylenically unsaturated compound having a functional group which reacts with a carboxyl group, 30 to 91.8 pts.wt. styrene or α-methylstyrene and 5 to 40 pts.wt. acrylonitrile or methacrylonitrile. Here, 100 pts.wt. copolymer particle having a number average particle size of 0.1 μm to 100 μm, wherein at least 10% of the carboxyl group is neutralized by an alkaline metal compound, is dispersed in 50 to 200 pts.wt. plasticizer.