Abstract: The marine dissolved organic carbon (DOC) reservoir is one of the most important parts of the Earth's carbon cycle. Its vast storage capacity and slow turnover rate make it a key buffering system for regulating global climate. The climatic effects of the DOC reservoir over long timescales are primarily reflected in anomalies recorded in marine carbon isotopes. The development of box models has enabled multi-scale coupled simulations of DOC production, transport, and degradation processes. However, ideal parameterization schemes, such as bacterial degradation efficiency and photodegradation efficiency, can still be optimized through in situ observations and culture experiments to achieve more realistic simulation results. Research on the climatic effects and geological evolution of the DOC reservoir remains quantitatively underdeveloped. Future studies shall focus on specific environmental parameters, such as the apparent degradation coefficient of DOC, to enhance the accuracy and confidence of simulations and facilitate the reconstruction of the geological evolution of the DOC reservoir over long timescales, offering new perspectives for understanding the relationship between carbon cycle and climate change.