The invention provides a medicine sub-packaging device. A plurality of medicine measuring barrels which correspondingly communicate with medicine dispensing holes are fixedly connected onto supporting plates in a sealed manner; hoisting blocks are arranged above the supporting plates; a plurality of medicine measuring grooves which correspond to the medicine measuring barrels and are through up and down are formed in the hoisting blocks along the thickness direction of the hoisting blocks; the medicine measuring barrels are in sliding connection into the medicine measuring grooves up and down in the sealed manner; a hoisting sliding sleeve is fixedly connected with the side faces of the hoisting blocks; a hoisting sliding rod is in sliding connection into the hoisting sliding sleeve up and down; the lower end of the hoisting sliding rod is fixedly connected with one supporting plate; the side wall of the hoisting sliding sleeve is in thread connection with a positioning bolt; the inner end of the positioning bolt ejects against the outer side of the hoisting sliding rod; drawing sliding rails which are arranged in pair and are arranged transversely are fixedly connected under the supporting plates; and a medicine dispensing separation plate for blocking the medicine dispensing holes is connected between the drawing sliding rails in a sliding manner. Connecting plates are fixedly connected below the supporting plates; a plurality of through holes which correspond to the medicine dispensing holes up an down are formed in the connecting plates; and each through hole is fixedly connected with a medicine dispensing barrel for connecting a medicine bag and the medicine dispensing separation plate is located above the medicine dispensing barrels.