The method of producing 4-fluoroethylene carbonate (FEC), in which ethylene carbonate (EC) reacts with a mixture of fluorine and nitrogen gases, includes feeding a mixture gas of fluorine gas and nitrogen gas into a reactor having ethylene carbonate charged therein, so as to react the ethylene carbonate with the mixture gas of the fluorine gas and the nitrogen gas. The mixture gas fed in the reactor is regulated to have a desired bubble size while passing through a gas bubble regulating column, in which a packing for a packed column is packed. In the method, EC directly reacts with F2/N2 mixture gas to produce FEC, thus a purification process is simple and it is possible to produce FEC at high conversion efficiency and selectivity.