To provide a two-pack mixing coating device which is simple in its structure and in which there is not hardening of coating in a coating path of a coater.

This device has a coater 2 consisting of an inner pipe 21, an outer pipe 22 disposed on the outer periphery thereof, a rotatable shaft 23 disposed on the outer periphery of the outer pipe, a bell cup 24 attached on the head of the shaft, and a cover 25 disposed on the head of the bell cup and also it has a main agent tank 4 connected to the inner pipe through a main agent pipe 41 and a curing agent tank 5 connected to the inner pipe through a curing agent pipe 51. A main agent 40 fed to a main agent path in the inner pipe from the main agent tank and a curing agent 50 fed to a curing agent path between the inner pipe and the outer pipe from the curing agent tank are mixed within the bell cup 24 rotated at high speed to spray the mixture from the bell cup 24.