This study applies a neural network technique to produce maps of oceanic surface p CO 2 in the Prydz Bay in the Southern Ocean on a 0.1 longitude × 0.1 latitude grid based on in-situ measurements during the 31th CHINARE cruise for February 2015. The study area was divided into three regions, Open-ocean region, Sea-ice region and Shelf region. The distribution of oceanic p CO 2 was mainly affected by physical process in the Open-ocean region where mixing and upwelling became the main controls. While in the Sea-ice region, oceanic p CO 2 changed sharply due to the strong change of seasonal ice. For the Shelf region, biological factor was the main control. The weekly oceanic p CO 2 was estimated using a self-organizing map (SOM) by four proxy parameters (Sea Surface Temperature, Chlorophyll a concentration, Mixed Layer Depth, and Sea Surface Salinity) to resolve the nonlinear relationships under complicated biogeochemical conditions in Prydz Bay region. The reconstructed oceanic p CO 2 coincides well with the in-situ investigated p CO 2 from SOCAT, in the root-mean-square error of 22.14 μatm. Prydz Bay was mainly a strong CO 2 sink in February 2015 with a monthly averaged uptake of 18.7 ± 4.93 TgC. The oceanic CO 2 sink is pronounced in the Shelf region due to its lowest oceanic p CO 2 with peak biological production. Strong potential anthropogenic CO 2 uptake in the Shelf region will enhance the acidification in the deep water of Prydz Bay and affect the deep ocean acidification in the long run since it contributes to the formation of Antarctic bottom water.