Abstract: In this study, regional differences in precipitation between the northern and southern Tibetan Plateau (hereafter TP) are analyzed based on the China gauge-based monthly gridded data (CN05.1) and the precipitation dataset provided by the Global Precipitation Climatic Center (GPCC) for the period 1979 to 2015. Responses of interannual variation in precipitation to the Arctic Oscillation (AO) anomalies are explored using the methods of regression analysis and composite analysis etc. The results indicate that there exists a close relationship between winter precipitation over the northern and southern TP and the AO. However, interannual variations of precipitation in the northern and southern TP and their response mechanisms to AO anomalies are different. Besides, the main synoptic systems that influence winter precipitation in the two regions are also different. The variation of winter precipitation in the northern TP is mainly related to the East Asian winter monsoon, which weakens (strengthens) with southeasterly (northwesterly) anomalies in the troposphere when the AO is in positive (negative) phase. The southeasterly (northwesterly) anomalies are favorable (unfavorable) for water vapor transport from the western Pacific to the northern TP, leading to increases (decreases) in precipitation there. In contrast, winter precipitation anomalies in the southern TP are mainly caused by the southern branch trough. When the AO is in positive (negative) phase, the southern branch trough reinforces (weakens), which is (is not) conducive to the transport of warm and moist water vapor from the Bay of Bengal to the TP and the convergence (divergence) in the lower troposphere. Meanwhile, the ascending (descending) motion enhances, resulting in increased (decreased) precipitation in the southern TP. In summary, the response mechanisms of winter precipitation in the northern and southern TP to the AO anomalies are different in that the AO mainly affects winter precipitation in the northern (southern) TP by affecting the East Asian winter monsoon (southern branch trough). Note that compared to positive AO anomalies, the impact of negative AO anomalies is more significant.