Provided in the present invention is a vinylidene fluoride copolymer. Same is acquired via a polymerization reaction taking place at conditions of 30-100° C. and 2-7 MPa with vinylidene fluoride, tetrafluoroethylene, and perfluorinated dioxole or C1-4 alkoxy-substituted perfluorinated dioxole as raw materials, with an initiator added into an emulsion consisting of water, fluorinated emulsifier, a chain transfer agent, a pH regulator, and an antifouling agent, and then via steps of separation, purification, refinement, condensation, washing, drying, and granulation, where the molar ratio of vinylidene fluoride, tetrafluoroethylene, and perfluorinated dioxole or C1-4 alkoxy-substituted perfluorinated dioxole is 13-17:2-4:1-3. The vinylidene fluoride copolymer of the present invention provides excellent transparency, flexibility, and solubility, is widely applicable in optical apparatus such as lenses, and is for use in specialty films in the fields of solar panels and of capacitors as a fuel cell membrane, a transparent and tough coating, and a large-sized blown object.