Provided is a method of producing a nickel nanopowder, the method capable of preventing coagulation between particles and, accordingly, providing a nickel nanopowder having a small average particle size and a low coagulation rate. According to an embodiment of the present invention, the method of producing a nickel nanopowder includes providing a nickel salt and a shell-forming material; nucleating and growing nickel core particles from the nickel salt; forming a shell layer on surfaces of the nickel core particles using the shell-forming material; and removing the shell layer to form the nickel nanopowder.