Crystal orientation and yield strength are studied for a magnesium ingot continuously cast by the OCC process. The ingot consists of elongated subgrains parallel to the solidification direction. The disorientation angles between neighboring subgrains are about 2 degrees. Overall orientations of the subgrains in the ingot are well aligned and the ingot has a monocrystal-like structure. Anisotropy of plastic deformation is observed for specimens cut from the ingot, which is similar to that in magnesium monocrystals. It is found that the presence of subboundaries increases the critical resolved shear stresses for the basal-slip system.