Abstract: The deep carbon cycle significantly influences atmospheric CO₂ concentrations, playing a critical role in global climate change and Earth’s habitability. At convergent plate margins, surface carbon undergoes deep cycling through plate subduction via a series of processes such as metamorphic dehydration and/or partial melting, crust-mantle interactions, and magmatism. This paper presents a systematical review on the carbon reservoirs of the mantle and crust, the decarbonation mechanisms in subducting slabs, carbon sequestration during crust-mantle interactions, and the role of magmatic activity at convergent plate margins in deep carbon cycling and carbon release. It also outlines the footprints of deep carbon cycling in oceanic subduction zones and continental collision zones, along with the factors affecting carbon release, sequestration, or migration in various processes.