Abstract: This paper synthesizes and reviews progress in recent research on the processes and physical mechanisms involved in the influence of the western Pacific warm pool on the monsoon trough and tropical cyclone and typhoon (TCs) activity over the western North Pacific. Specifically, recent studies on the characteristics of the variation in the western Pacific warm pool thermal state and convective activity around the Philippines, along with the processes and physical mechanisms influencing the effect of this variation on the South China Sea summer monsoon onset and intraseasonal and interanual variabilities of the western Pacific subtropical high, are summarized. Then, recent studies on the processes and physical mechanisms by which the western Pacific warm pool thermal state influences the interannual and interdecadal variabilities of TCs activity over the western North Pacific via the monsoon trough are also systematically reviewed. Finally, a number of scientific problems requiring further study are highlighted, related to the thermal and dynamical effects of the western Pacific warm pool on the monsoon trough and TC activity over the western North Pacific.