Understanding the paleoenvironmental conditions of a watershed is essential for evaluating human impacts on the current environment, guiding the restoration of degraded ecosystems, and predicting the future climate changes and their impact. This chapter will cover: (1) methods for reconstructing paleoclimates and paleoenvironmental conditions; (2) the uplift of the Tibetan Plateau and its impact on the climates of the Yellow River basin; (3) the paleoclimates and paleoenvironmental conditions of the Loess Plateau; and (4) the migration patterns of the lower stream channels of the Yellow River.