Provided are a method of manufacturing an olefin having 2 to 4 carbon atoms including: reacting a catalyst with synthesis gas through a Fischer-Tropsch reaction, thereby obtaining the olefin having 2 to 4 carbon atoms, in which the catalyst is a catalyst obtained by reducing the iron ion and the cobalt ion in a dispersion liquid or a solution containing the iron ion, the cobalt ion and a dispersant that interacts with the iron ion and the cobalt ion, and a method of manufacturing propylene, which uses the above manufacturing method.