PURPOSE: To enable the extension of a seed moving stroke for pulling up a single crystal of length longer than heretofore with an apparatus for growing a semiconductor single crystal of a shaft system without having a cable winding up mechanism.

CONSTITUTION: A wire 2 supporting a seed holder 3 in balance is connected to the bottom end of a short force bar connected to a load cell 1 in the case of the growth device having a crystal weight type diameter control system. Three pieces of pulleys 7, 8, 9 which are freely movable in a horizontal direction are disposed on the right and left outer sides of bellows 6 enclosing the upper space of a chamber 5. The bellows 6 is compressed upward to horizontally move the pulleys 7, 8 toward the left until the pulleys come into contact with the wire 2 at the time of taking the single crystal 4 out of the furnace. The pulley 9 is moved further horizontally toward the left after the pulley comes into contact with the wire 2. As a result, a part of the wire 2 is pulled toward a transverse direction between the pulley 7 and the pulley 8 and the single crystal 4 is correspondingly pulled upward and, therefore, the single crystal of the size longer than heretofore is taken out.