A portable typewriter particularly adapted for juvenile use comprises a plurality of types, a plurality of key levers each of which has a key and arm, an universal plate actuated by any one of the poeration key levers, a carriage in which a platen is provided for supporting paper, a ribbon cartridge in which a typewriter ribbon is loaded, and ribbon cartridge actuating means connected to the universal plate and adapted to shift the typewriter ribbon cartridge in a direction parallel to the axis of the platen to a typing position and, at the same time, to advance the typewriter ribbon when one of the keys is operated. The cartridge actuating mechanism is arranged to be shiftable vertically independently of its movement parallel to the axis of the platen. The typewriter ribbon cartridge and the actuating means are adapted to easy manufacture, and to allow the extensive use of plastics in the construction.