Tropical cyclones are a common type of severe weather event that can cause significant economic losses and serious casualties. Therefore, improving the forecasting capability of tropical cyclones, especially the intensity forecasting capability, has always been a key issue. In recent years, oceanic submesoscale processes caused by tropical cyclones have received widespread attention and research. However, there are still gaps in the research on the role and mechanism of oceanic submesoscale processes in the intensity of tropical cyclones. Based on the COAWST coupled model, we conducted a case study experiment on Typhoon KRATHON, which developed in the Luzon Strait in 2024. The results show that the oceanic submesoscale process has an enhancing effect on this case. After 00:00 on September 30, the maximum wind speed increased by 40% and the minimum air pressure increased by 17%. Oceanic submesoscale processes can rapidly adjust the upper ocean following a typhoon, suppressing the cooling of the upper ocean caused by typhoon stirring. This manifests as a weakening of the cold wake intensity and a faster recovery of the upper ocean temperature beneath the typhoon surface. Therefore, warmer and thicker seawater can provide more energy for the subsequent development of the typhoon. During typhoon development, sensible and latent heat fluxes increase accordingly, leading to KRATHON's development into a stronger typhoon.