Recently, at the Shih Chai Shan (石寨山) site in Yun-nan (雲南), South-West China, a certain number of metallic drums have been discovered. They are the most typical remains of the Dong-So'n culture. The writer believes that these drums can largely be devided into two groups from a functional point of view. Those that seem to have a full function of the musical instrument form the first group, and those that appear to have no such function form the second. The drums which come under the first group are characterized by their shape and the ornamental figures of bird-men, boats, flying birds, circles with tangents, zigzag-filled bands, central star and so on, engraved on the surface and around the body. They belong to what Heger called Type I. The second group can be distinguished from the first for the existence of various human and animal figurines and small drums casted on the beating surface: this character deprives the drums of this group of any musical function. They may be considered as mortuary instruments. Probably, the writer supposes, the second group drums are derivations from the first group ones. By considering the corelation between the metallic drums and other bronze remains, and by their typological studies, the production of the first group drums can be dated to the Chan Kuo (戦国) period, between the 4th and the 3rd centuries B. C. This can be related to the south-ward penetration of the Ch'u (楚) culture of the Central China. The second group drums seem to belong to the Han (漢) period from the 2nd or the 1st century B. C. They can be considered to have some connections with the Han culture of the North China. The derivation and the development of the second group drums, which served as mortuary musical instruments, can easily be understood, when we think of the contact between the culture of the Han dynasty following the conquest of Emperor Wu (武帝) and the aboriginal Dong-So'n culture. From the viewpoint of mortuary use of these instruments, we can recognize a certain resemblance between the second group drums and the small drums of the Dong-So'n site in North Indo-China. And the writer thinks that this accidental resemblance is an extremely interesting phenomenon in the cultural aspect of history.