Sea spray generated by wave breaking under high wind speeds strongly influences air-sea turbulent heat exchange. Nowhere is this process more critical than the Southern Ocean where the most extreme wave climate on Earth is located. However, current existing gridded air-sea heat flux datasets lack representation of sea spray-mediated component, which lead to a major problem in assessing and understanding the role of sea spray in the Southern Ocean. Here, we present a new gridded dataset of spray-mediated latent and sensible heat fluxes over the Southern Ocean that incorporates a full sea spray microphysical model, which considers spray generation that depends on regional wind and wave states. Our data allows a quantitative assessment of the spray-mediated contribution to the total air-sea heat flux exchange. Climatologically, spray-mediated heat fluxes range from 0.04 to 39.6 W m<sup>-2</sup>, with large fluxes in the circumpolar region (50° S–60° S), especially in the Indian sector during austral winter. Validation of an extreme cyclone shows that, within the high wind sector of the cyclone, spray-mediated heat fluxes double the regional fluxes compared to conventional bulk algorithm estimates. This dataset serves a critical foundation for examining the Southern Ocean’s role in the global energy budget.