A manufacturing method of a nitrided steel member and the nitrided steel member include: performing a nitriding treatment on a steel member made of a carbon steel or an alloy steel in an atmosphere of a nitriding treatment gas in which when the total pressure is set to 1, a partial pressure ratio of NH3 gas is set to 0.08 to 0.34, a partial pressure ratio of H2 gas is set to 0.54 to 0.82, and a partial pressure ratio of N2 gas is set to 0.09 to 0.18, at a flow speed of the nitriding treatment gas set to 1 m/s or more, at 500 to 620° C.; and thereby, forming an iron nitride compound layer having a thickness of 2 to 17 μm on a surface of the steel member.