A production process of a sulfide containing nickel and cobalt by adding a sulfurizing agent under pressurization into an aqueous solution of sulfuric acid containing nickel and cobalt, which is capable of recovering nickel and cobalt as a sulfide in high yield, as well as enhancing the utilization efficiency of hydrogen sulfide gas.A production process of a sulfide containing nickel and cobalt by adding a sulfurizing agent under pressurization into an aqueous solution of sulfuric acid containing nickel and cobalt, characterized by supplying, as the above sulfurizing agent, hydrogen sulfide gas into the vapor phase of inside of a reactor, as a major sulfurizing agent, as well as, by supplying an aqueous solution containing a sodium hydrosulfide, which is recovered by absorbing unreacted hydrogen sulfide gas, which is discharged from inside of the reactor in producing the above sulfide, with an aqueous solution of sodium hydroxide, into the liquid phase.