Growth of B. megaterium QM B 1551 in Schaeffer's medium was inhibited by more than 5 μM cadmium chloride added to the medium. Cells could not grow in the presence of 50 μM cadmium chloride. The inhibition of growth of cells by cadmium chloride was suppressed by the addition of manganese chloride. Cadmium chloride was incorporated into cells. On the other hand the content of manganese in cells decreased. A large portion of cadmium of cells existed in the soluble fraction of cell free extracts. The greater part of cadmium was bound to proteins whose molecular weights were more than 200000. Activity of phosphoglycerate mutase obtained from cells grown with cadmium chloride was less than that of cells without cadmium chloride. It is discussed that there may be some relationship among a decrease in manganese content of cells, phosphoglycerate mutase activity and inhibition of growth of cells by cadmium chloride.