By using the NCEP/NCAR reanalysis daily dataset from 1979 to 2013, the circulation characteristics of the Aleutian Low on low-frequency scale in winter was investigated, moreover, the related synoptic transient eddy forcing mechanisms of the formation and maintenance of low-frequency variability of the Aleutian Low are also discussed. Results show that the low-frequency variability of the Aleutian Low in winter exhibits the evolution of an abnormal cyclone/anticyclone in the North Pacific basin area at 850 hPa, which means that the Aleutian Low on the low-frequency scale experiences strengthening, weakening and then returning to normal state process. It is the low-frequency cold center establishing in Northwest Pacific and gradually moving to the east that characterizes the temperature fields at 850 hPa. The analysis on the anomalous change of synoptic-scale transient eddy activities and transient eddy forcing shows that the transient eddy dynamic forcing anomalies becomes negative during the anomalous strengthening phase of the Aleutian Low, which is beneficial to establish and maintain the anomalous space type of the Aleutian Low on low-frequency scale. The anomalous fields of temperature tendency caused by the transient thermal forcing anomalies varies from positive value in the South Pacific of 40°N and to negative value in the North of 40°N in the middle of North Pacific, and the southern positive anomalies suppresses and weakens the expanding of low-frequency cold center to the south to a certain extent.