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This study investigates the influences of intraseasonal oscillation on two types of regional extreme consecutive dry days events (RECDD) in spring over Southern China (SC). For type‐1 RECDD occurring in entire SC, the 7–25 days and 25–90 days high over Lake Balkhash‐Baikal are important. The 7–25 days high first causes lower‐tropospheric northerlies and moisture deficit in SC, then propagates to Yangtze River Basin and causes lower‐tropospheric warming and decaying moisture deficit in SC. These processes favor dry condition in SC for 1 week. In comparison, the 25–90 days high and associated lower‐tropospheric warming and moisture deficit in SC favor dry condition there for more than one week. For type‐2 RECDD occurring in the southern part of SC, the 7–25 days and 25–90 days high over Northeast Asia are important. The 7–25 days high contributes for one week. It first causes lower‐tropospheric anticyclone around the East China Sea and south‐negative–north‐positive moisture pattern in SC, then propagates to the Sea of Japan and causes lower‐tropospheric south‐warming–north‐cooling pattern and decaying south‐negative–north‐positive moisture pattern in SC. In comparison, the 25–90 days high and associated lower‐tropospheric south‐warming–north‐cooling pattern and south‐negative–north‐positive moisture pattern in SC favor south‐dry–north‐wet pattern there for more than one week. Moreover, the 7–25 days low and decaying 25–90 days high over Lake Balkhash‐Baikal, concurring with 7–25 days low over Bay of Bengal, favor the end of type‐1 RECDD; the 7–25 days low and decaying 25–90 days high over Northeast Asia favor the end of type‐2 RECDD. Plain Language Summary: The extreme consecutive dry days with long duration could increase the risk of drought, even if the mean precipitation does not show significant change. In this study, we identify two types of regional extreme consecutive dry days events in spring over Southern China (type‐1 occurs in entire Southern China, type‐2 occurs in southern part of Southern China), with the aim of understanding the direct physical processes responsible for the persistence of extreme consecutive dry days. The results show that anomalous high over Lake Balkhash‐Baikal/Northeast Asia on two time‐scales (7–25 days and 25–90 days) are important for the persistence of type‐1/type‐2 events. In comparison, the 7–25 days high favors the persistence of regional events for approximately one week, whereas the 25–90 days high favors longer. Moreover, the 7–25 days low and decaying 25–90 days high over Lake Balkhash‐Baikal, combined with 7–25 days low over Bay of Bengal, provide a favorable condition for the end of type‐1 events. The 7–25 days low and decaying 25–90 days high over Northeast Asia favor the end of type‐2 events. Key Points: Two types of regional extreme consecutive dry days events in Southern China (SC) are identified in this study7–25 days high over Lake Balkhash‐Baikal/Northeast Asia favors type‐1/type‐2 events for one week, and 25–90 days high over there favors longer7–25 days low over Lake Balkhash‐Baikal/Northeast Asia, combined with decaying 25–90 days high there, favors the end of type‐1/type‐2 events [ABSTRACT FROM AUTHOR]