Abstract: Large-scale patterns of species diversity are one of the most important and attractive issues for ecology and biogeography. Many hypotheses have been proposed to understand the mechanisms that shape and maintain the diversity patterns. Among them, the energy hypothesis, which focuses on the influence of energy on species diversity, has generated the most attention. Based on the forms of energy and the mechanisms of energy effects on diversity patterns, five versions of the energy hypothesis have been recognized, i.e. productivity hypothesis, water–energy dynamic hypothesis, ambient energy hypothesis, freezing tolerance hypothesis, and metabolic theory of ecology. The current paper reviews the development of the energy hy-pothesis, and then presents the context, energy forms, variables, predictions, and underlying mechanisms for the five versions of the energy hypothesis. Furthermore, we discuss the advantages, shortcomings, and chal-lenges of each version of the energy hypothesis.