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An analysis of the Ishii ocean heat content （OHC） in the tropical Indian Ocean from the surface to 700-m depth shows that the OHC changes dramatically on the interannual timescale in the Indian Ocean. The first mode of empirical orthogonal function （EOF1） of the OHC shows that there is a strong air-sea interaction pat- tern in the Indian Ocean with a positive （negative） loading in the east and a negative （positive） loading in the west. This seesaw oscillation pattern influences the summer precipitation in China with a North-South reversed distri- bution. Composite analysis shows that during a positive （negative） OHC episode, an anomalous cyclonic （anti- cyclonic） circulation over the western Pacific and South China weakens （enhances） the monsoonal northward flow in the lower troposphere; meanwhile, anomalous merid- ional circulation connects the descending （ascending） branch over the Southeast Indian Ocean and the ascending （descending） branch in South China as well as a descend- ing （ascending） branch over North China. Analysis of the mechanism behind these features suggests that （1） the accumulation of OHC-induced vorticity is related to the wave activity over the mid-latitudes and that （2） the me- ridional teleconnection induced by the Indo-Pacific air-OHC interaction appears over East Asia and the west- ern Pacific. Both of these patterns can cause summer pre- cipitation anomalies in China.