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This study investigates the intermodel spread of changes in the Eurasian winter surface air temperature (SAT) based on Coupled Model Intercomparison Project 6 (CMIP6) and explains it from the perspective of circulation under shared socioeconomic pathway 2–4.5. Results show that the leading intermodel spread of Eurasian SAT change, derived from the intermodel empirical orthogonal function analysis (EOF), is characterized by a warming pattern of SAT change. This warming pattern is associated with the changes in the weakened Siberian High and Aleutian Low, the weakened subtropical jet, the poleward polar jet, and the tilting trough. The combination of these circulations has prevented the intrusion of the cold air to the south and therefore results in the warming SAT change pattern. Their relative contribution weights of the weakened Siberian High and Aleutian Low, the tilting East Asian trough, the weakened subtropical jet, and the poleward polar jet are 12.73%, 20.43%, 30.24%, 20.96%, and 15.64%, respectively. All these changes may be traced to the warm sea surface temperature (SST) changes in the western North Pacific and tropical Atlantic Ocean, via the meridional temperature gradient and wave trains, respectively. These warmings would be the potential metrics for reducing the intermodel uncertainties of the winter SAT projection at the end of the 21st century over the Eurasian continent. Plain Language Summary: There are still large intermodel uncertainties in the projection of the winter SAT over the Eurasian continent. In this study, the intermodel EOF is utilized to derive the intermodel spread in the winter SAT change at the end of the 21st century over the Eurasian continent. The leading mode is a warming pattern over Eurasia, which is closely related to the large‐scale circulations, including the changes in the weakened Siberian High and Aleutian Low, the tilt of the East Asian trough, the weakened western subtropical jet, and the northward shift of the eastern polar front jet. All these changes may be traced to the warming in the western North Pacific and the tropical Atlantic. Our findings provide a perspective to improve the projection of Eurasian winter SAT. Key Points: The leading intermodel spread in winter surface air temperature change at the end of the 21st century over the Eurasian continent is a warming pattern from the CMIP6 modelsThe large‐circulation changes in the sea‐level pressure, the tilting trough, and jets are highly associated with this intermodel spreadAll these changes might be traced to the warm SST changes in the western North Pacific and the tropical Atlantic [ABSTRACT FROM AUTHOR]