The history of abrupt climate change in East Asia is often discussed from hydroclimate proxies that record the isotopic composition of rainfall. However, the underlying mechanisms remain obscure because water-isotope proxies respond to a wide variety of environmental variables. Here, we investigated millennial-scale climate variability in East Asia over the past 400,000 years using paired foraminiferal oxygen isotope and Mg/Ca records from the East Asian continental margin, thereby resolving variance into temperature and rainfall components. We found that the temperature and rainfall variabilities are largely asynchronous, with times when the global climate shifts from interglacial to glacial periods being the notable exception. These findings highlight the importance of both mean global state and magnitude of North Atlantic variability in determining the East Asian climate. Without a strong North Atlantic forcing, the regional feedback system might generate asynchronous temperature and rainfall variations, which is the background climate feature in East Asia.