Small mountainous rivers (SMRs) are important conveyors of the land-to-ocean organic carbon export. However, relatively few studies have focused on dissolved organic carbon (DOC) compared to particulate organic carbon. In a long-term project (2002 to 2014), stream DOC was monitored in three neighboring subtropical small mountainous rivers of Taiwan. The objective was to highlight the high DOC yield in SMRs and reveal the implications for global warming. The mean DOC concentration of the studied systems (＜1.0 mg L-1) is ranked in the lowest 1% world's rivers. However, mean DOC yield (~30 kg ha-1 y-1) is ranked in the top 30%. A positive relationship exists between temperature and DOC concentration which is 30% higher in wet season than in dry season. And typhoon-induced discharge boosted the DOC concentration by 5 times. More than 60% of annual DOC export was flushed off in the wet (warm) season. Moreover, up to 29.5±13.8% of the annual DOC export was accounted for by typhoon events, which the invasion time occupied ~3% of the monitoring period. We conclude that higher temperature and typhoon events are important drivers of the land-to-ocean export of dissolved organic matter. Predicted future increases in temperature and frequency/magnitude of typhoon events will likely elevate streamwater DOC concentration and accelerate the transport of terrestrial carbon to the ocean.