A heating cooking appliance and a burner system of the same are provided. A nozzle and a mixing tube can be stably fixed, and relative position of components can be aligned with high precision even if the heating cooking appliance has a narrow internal space. Thus, operational reliability of the heating cooking appliance is improved, and an operator can easily assemble the burner system. To this end, a nozzle coupling part is configured to fix a position of a nozzle, and a mixing tube coupling part is configured to fix a position of the mixing unit. The nozzle coupling part and the mixing tube coupling part are partially coupled to achieve a precise relative positional relation between the nozzle and the mixing tube.