PROBLEM TO BE SOLVED: To provide a manufacturing device for hydrocarbons and a manufacturing method for hydrocarbons and in which a wax is prevented from adhering to a cooling vessel of a gas-liquid separation device in unsteady operation.SOLUTION: The manufacturing device for hydrocarbons is operated by Fischer-Tropsch synthesis reaction using a bubbling-tower-type slurry bed reaction vessel 30 which retains a slurry containing catalyst particles and liquid hydrocarbons in the interior of the vessel. The manufacturing device for hydrocarbon is provided with a gas-liquid separation device 36 which cools hydrocarbons in gaseous form extracted from a gaseous phase section 82 of a reaction vessel 30, causes some of the hydrocarbons to liquefy, and separates gas and liquid. A light liquid hydrocarbon supply line 91 which supplies light hydrocarbons is provided between a downstream light liquid hydrocarbon line, which is a line downstream of a final-stage gas-liquid separation unit 86 of the gas-liquid separation device 36 and through which flow light hydrocarbons with a cloud point lower than the outlet temperature of a cooling vessel 86a in the final-stage gas-liquid separation unit 86, and an upstream line upstream of the final-stage gas-liquid separation unit 86 of the gas-liquid separation device 36.