A drum type washing apparatus and a method of processing the wash using the drum type washing apparatus wherein they have a characterizing feature which consists in that the peripheral wall of a rotary drum made of a perforated plate is configured in the form of a wall having a single corrugated portion or a plurality of corrugated portions which do not intersect the direction of centrifugal force generated by rotation of the rotary drum at right angles. Further, they have other characterizing features which consist in that the apparatus is provided with a liquid injecting nozzle and/or a gas blowing nozzle and/or a hot air blowing nozzle for allowing liquid and/or gas and/or hot air to be injected and/or blown into the interior of the rotary drum whereby a period of time required for performing steps of washing, dewatering and drying the wash in the rotary drum can be shortened. Moreover, they have another characterizing feature which consists in that the rotary drum is rotated and air is blown into the interior of the rotary drum while a door is kept opened so that the wash can be discharged from the rotary drum at a high efficiency under the influence of force generated by flowing of the air.