The method for producing silicon metal and porous carbon from rice hulls is provided. The method comprises a first step S1 of producing a rice hull charcoal M2 containing SiO2 and C by heat treatment of rice hulls M1; a second step S4 of exposing the rice hull charcoal M4 to at least any one of heated first inert gas G2 or reducing gas to produce SiC; a third step S5 of exposing SiC to a heating atmosphere containing Cl2 gas to produce SiCl4 and porous carbon P1; a fourth step S7 of reacting SiCl4 and Zn to produce silicon metal P2 and ZnCl2; and a fifth step S9 of electrolyzing ZnCl2 to produce Zn and Cl2 gas. The Cl2 gas in the fifth step S9 is used in the third step S5, and Zn in the fifth step S9 is used in the fourth step S7.