The authors have studied the oxygen and carbon ssotopic compositions of the carbonate wall rocks from the Dahongshan mining area, Yunnan Province and, combining with geological features, laid emphasis on the study of the underlying marble which is most greatly affected by the ancient volcanic erup- tion. The analyses of 31 samples indicate that there is a distinct pattern for the variation of oxygen and carbon isotopic compositions, which is in coinci- dence with the pattern of the central-volcanic eruption and volcanic neck emplacement inferred from geological and petrological studies. The oxygen and carbon isotopic data also show that the carbona.tite rocks in the Dahongshan area were most likely formed by melting of the marble. As a supplement to the data appeared in the paper[1], the oxygen and carbon isotopic data of 13 siderite samples are presented here. They may be characteristic of the moder- ately metamorphosed volcanic-sedimentary siderites.