The loess-paleosol-red clay sequence in the Chinese Loess Plateau has attracted attention for its potential in recording late Cenozoic climatic changes over northern China, although the details of the climatic implications of the proxies (for example, magnetic susceptibility) and the reconstructed summer monsoon changes remain unclear. Here we report on a new section from Baishui, in Gansu province and compare it with the Lingtai and Jingchuan sections. By correlating the magnetic susceptibility from these sections, we show that there is a clear systematic decrease of the magnetic susceptibility in the red clay deposits from the southeast (Lingtai section) to the northwest (Baishui section). This result suggests that the climatic parameters (probably precipitation) had a decreasing northwestward gradient during the red clay deposition. This climatic pattern is similar to the present condition, implying that the influence of the East Asian summer monsoon on the Chinese Loess Plateau has persisted from at least 6 Ma.