This method for producing a compound uses a continuous tank reactor which is provided with two or more reaction tanks for producing the compound and with a reaction liquid feeding pipe that feeds a reaction liquid from an upstream reaction tank to a downstream reaction tank, said method being characterized in that the Reynold's number of the reaction liquid that flows in the reaction liquid feeding pipe is configured to be 1800-22000. Furthermore, this compound production system is used in said method for producing a compound, and is formed by housing at least one of the reaction tanks in a portable container.