Almanacs (tongshu in Chinese) were a ubiquitous feature of the social landscape in both China and the West from at least the seventeenth century onward, offering a rich topic for comparative analysis. They serve as a valuable index of popular beliefs, moral values, and cultural priorities. They also provide a window on the processes of social, political, and intellectual change in both environments. Using a comparative approach, this study tries to illustrate how the almanacs in both China and the West have mirrored their respective cultural environments and how the history of almanacs in both societies reflects the powerful changes brought about by the scientific and philosophical revolutions of seventeenth-century Europe. At the same time, it also seeks to show the limits of these revolutionary developments, the ways in which traditional beliefs and practices have persisted up to the present in each society, and the reasons for their persistence.