The recognized linkage of climatic events to the Earth's orbital variations has provided the basis for establishing time scales of Pleistocene climatic records. Most of the classic orbital tuning methods developed so far, however, need visual judgements to add new time control points into the climatic records, thus being time-consuming and hindering the construction of high resolution climatic time series. In this study, we propose to use the Dynamic Optimization method to overcome the shortcomings. With this technique, the additional time control points can be automatically added into the climatic records, and a best age for each of the climatic data can be calculated. Results of a case study conducted on the Baoji loess section show that the automatic orbital tuning method can lead to a much better agreement of climatic time series with theoretical changes in the orbital elements relative to the classic ones. ¿ 1998 American Geophysical Union