Angular distributions of sputtered Si atoms from polycrystalline Si targets were measured for Ar+ions of 3 and 10 keV, at angles of incidence of 0° (normal incidence) and 60°. The results were compared with the theoretical ones obtained from Monte Carlo calculations by Kangetal. Theory describes qualitatively the experimental results fairly well. Some discrepancy between the theoretical and experimental results was, however, found in the preferred ejection angles. The preferred ejection angle of the experimental results for 10 keV at angle of incidence of 60° agrees very well with that suggested by the universal curve of the correlation between the preferred ejection angle and sputtering yield, which has been proposed by Betzetal.