A process for producing a vinyl chloride polymer by polymerizing a monomer comprising vinyl chloride by suspension polymerization in a polymerization vessel on the inner wall surface of which a coating of a polymer scale preventive agent is formed, comprising the steps of applying a high-speed shearing force to a mixture comprising water, the monomer, a polymerization initiator, and (A) a dispersant comprising a partially saponified polyvinyl alcohol having a specified average degree of polymerization and a specified degree of saponification plus (B) a dispersant comprising a hydroxypropylmethylcellulose which has a specified methoxyl substitution degree, a specified hydroxypropoxyl substitution degree, and a specified viscosity and subjecting the mixture to said suspension polymerization. A vinyl chloride polymer having an average particle diameter of 200 to 600 .mu.m and a narrow particle size distribution and excellent in plasticizer take-up, etc. is provided.