1925年11月底，奉軍將領郭松齡率部從山海關回師瀋陽，企圖推翻張作霖在東三省的統治。一個月後，郭軍於遼河戰敗，郭氏被殺。郭氏之敗，論者多歸咎於日本關東軍的干預。本文將以中、日、英、蘇等國的檔案史料為基礎－探討日、蘇兩國在郭松齡事件的背景、成因和經過，以及日、蘇兩國在此事件中的角色，並重新檢視雙方勝負原委。本文認為，雖然日、蘇直接干涉事件，但郭軍戰略失誤和實際戰鬥對結果的影響實不可忽視。

ln November 1925, Guo Songling, the 60,000 strong men commander of the 3rd Army Group of the Fengtian Army, with a view to overthrowing the rule of Zhang Zuolin over the Chinese Northeast, suddenly marched back to Manchuria via Shanhaiguan from the China Proper. The attack was initially a success, with Guo's forces defeating the Jilin army near Lianshan on 5 December. However, when it was rumoured that Zhang Zuolin's regime was on the verge of collapse, Guo's army was somehow reversely overrun near the Liao River between 22 and 24 December. Japanese intervention had long been seen as the main reason for Zhang Zuolin's unexpected victory. Nonetheless, as more and more sources from China, Japan, and the Soviet Union have been made available in the recent years, there is a need to revisit the war, especially from geopolitical and military perspectives. This article attempts to deepen the study of warlord warfare during the 1920s in China by looking more closely at the role played by Japan and the Soviet Union before and during the Guo Songling Incident. It also suggests that although Soviet and Japanese interventions were important, the military factors and strategic mi stakes made by Guo himself were no less important.