An object of the present invention is to provide a method that enables the easy and efficient (high yield, high selectivity, low cost) preparation of a fluorine-containing olefin substituted with an organic group or groups from a fluorine-containing olefin.[Solution]The method for preparing a fluorine-containing olefin substituted with an organic group or groups, the method comprising a step of reacting a fluorine-containing olefin with an organic boron compound in the presence of an organic transition metal catalyst containing at least one transition metal selected from the group consisting of nickel, palladium, platinum, rhodium, ruthenium, and cobalt.