PURPOSE: To obtain paste sol directly from a vinyl chloride paste resin latex, by adding a specified oil-water separating agent in the production of a paste by adding a plasticizer drectly to the latex.

CONSTITUTION: In a process for producing paste sol directly from a mixed system consisting of a vinyl chloride paste resin latex and a plasticizer, an oil- water separating agent of formulaI(wherein a+b+c is an integer of 20W110, a+c/b is 0.01W0.4, a and b may be different from each other) or formula II (wherein X1+Y1WX4+Y4 are each an integer of 5W60, the arerage X/Y of the sum of Y1/X1WY4/X4 is 0.01W0.3, X1WX4 and Y1WY4 may have the same or different values) is incorporated in said mixed system. When these oil-water separating agents are added, water present in the latex is easily separated and the paste resin rapidly migrates toward the plasticizer layer. Paste sol can be easily obtd. by recovering the plasticizer layer.