The effects of various growth conditions on the yield percentage and orientation distribution of round-bar single crystals of zinc as grown by the Bridgman method have been studied. The experimental results obtained are as follows: — (1) In order to prepare the ingots, molten zinc was poured in air or in a vacuum or sucked up into soft glass molds and it was found that the vacuum casting is not practical and the suction casting is the best. (2) The higher is the purity of the material, the greater is the degree of success. The yield percentage falls very much when remelted zinc is used. (3) It has been found, from experiments on the production of single crystals from ingots made by sucking up, that the yield percentage decreases approximately linearly with increasing speed of lowering the mold. (4) Irrespective of the lowering speed of the mold, single crystals having such an orientation that the angle θ which the rod axis makes with the ⟨0001⟩ direction ranges from 75 to 85° are preferentially obtained. Single crystals of any orientation are produced at low lowering speeds, while those of small θ are hardly obtained at higher lowering speeds. (5) The purity of the materials does not seem to affect the orientation distribution.