We have collected data from the literature of the past two decades, and are carrying out for the first time a systematic, statistical study of all the documented long‐term x‐ray and optical light curves of x‐ray nova outbursts. This study can yield information which is critical to our understanding of these systems, as well as provide us with the necessary empirical ingredients for detailed theoretical modeling efforts. In this paper we discuss the basic properties of the light curves. Some distinguished features not well known before are also identified and briefly discussed. ©1994 American Institute of Physics.