To provide a novel conic mixing and drying machine and a mixing and drying method enabling effective operation of mixing, crushing, drying or the like.

A discharge device 3 for opening and closing a discharge opening 23 formed in a bottom of a treatment tank 2 is provided below the treatment tank 2, and the discharge device 3 is provided with a bottom partitioning plate 31 for partitioning a discharge side of the treatment tank 2. An opening 32 is formed in the partitioning plate 31, and a lid member 33 is provided for closing the opening 32. A space occupied by a treatment object matter W can be restricted to an inside space of the treatment tank 2, so that rotating blades 27 act on the matter W charged into the treatment tank 2 in a whole region. Thus, efficiency of mixing, crushing, or drying the matter W is enhanced.