Water dispersion of vinyl halide copolymer and film

A water dispersion of a vinyl halide copolymer, comprising

• a vinyl halide copolymer containing a structural unit derived from a vinyl halide monomer and a structural unit derived from a copolymerization monomer whose reactivity ratio r1 to vinylidene chloride is less than 0.7,
• wherein a mass ratio of the structural unit derived from the copolymerization monomer whose reactivity ratio r1 is less than 0.7 is 1 part by mass or more with respect to 100 parts by mass in total of the structural unit derived from the vinyl halide monomer, the structural unit derived from the copolymerization monomer whose reactivity ratio r1 is less than 0.7, and a structural unit derived from a copolymerization monomer whose reactivity ratio r1 to vinylidene chloride is 0.7 or more, and
• S1/(S1+S2) is 0 or more and 0.33 or less, where S1 is an area of a melting peak having a melting peak temperature of 170° C. or more, and S2 is an area of a melting peak having a melting peak temperature less than 170° C.