The present invention provides a kneading device 1 including a hopper 2 having a hopper body 4 that stores raw powder, and a mixer 3 that kneads material to be kneaded, which contains the raw powder, wherein the hopper 2 includes a stirring device 5 that stirs the raw powder in the hopper body, and a temperature-controlled air supply device 6 that supplies temperature-controlled air into the hopper body 4. This kneading device can stably prepare high-quality kneaded dough.