The present invention aims to provide a method of producing a fluoropolymer, especially a fluoropolymer essentially including a tetrafluoroethylene or chlorotrifluoroethylene unit, at a higher polymerization rate with improved efficiency, the method being capable of improving the moldability in extrusion molding and suppressing discoloration. The method of producing a fluoropolymer of the present invention includes producing a fluoropolymer by polymerizing tetrafluoroethylene or chlorotrifluoroethylene in the presence of a peroxydicarbonate. The peroxydicarbonate is represented by the formula: €ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒR-O-C(=O)-O-O-C(=O)-O-R wherein R's may be the same as or different from each other and individually represent a C4 alkyl group or alkoxy alkyl group.