PURPOSE: To obtain the title emulsion which can form a coating film with excellent water resistance, alkali resistance and weatherability by emulsion- polymerizing a vinyl aliph. tert. carboxylate and vinyl acetate.

CONSTITUTION: A vinyl aliph. tert. carboxylate of the formula (wherein R1, R2 and R3 are each a 1-6C alkyl) (e.g. a product obtained from an aliph. tert. caboxylic acid synthesized by reacting a mixture of polyolefins contg. 60wt.% or more isobutylene units with CO and water) and vinyl acetate are emulsion- copolymerized. A synthetic resin emulsion for coating which is suitable for a base of a coating which can form a coating film with excellent water resistance, alkali resistance and weatherability can be obtd. by a simple method of preparation.