The present invention provides a method of forming a solid projection having excellent mechanical properties on a metal member without supplying thermal energy from the outside, and a projection-forming device and a metal part having a projection manufactured thereby. The means for solving the problems is characterized in that the means is comprised of the processes of pressing the distal end 13a of the processing jig 13 having the hole-opening and a cavity 13b at the distal end against the surface of the metal member workpiece 111 and rotating the metal member workpiece 111 and the processing jig 13 in the direction relatively counter to the other to generate friction heat causing thereby plastic flow into the cavity through the hole-opening 13b.