Darcy’s law, which defines a linear relationship between the specific discharge and the hydraulic gradient, is commonly applied in many disciplines including hydraulic engineering, hydrogeology, environmental engineering, plant physiology, etc. However, Darcy’s law can become invalid under certain conditions where the flow velocity is larger or smaller than a critical value, thereby producing a non-Darcian flow. Non-Darcian flow problems have been found to be relatively more difficult to deal with due to associated high degree of nonlinearity. Nevertheless, in the past few decades, great progress has been made in the study of non-Darcian flow problems in several geoscience disciplines. In this review paper, we introduce the background of the laws governing non-Darcian flow behavior. We also review and elaborate on the recent developments on non-Darcian flow in high- and low-permeability media, and non-Darcian flow associated with heat transfer, gas phase non-Darcian flow and multiphase. In addition to these, three advanced topics (plant physiology, biological tissues, nanofluids), as well as new methods used in solving non-Darcian flow problems are presented. In each area, we introduce the related practical problems and then elucidate the theories and science to improve understanding of the issues. Finally, we highlight the current challenges on the subject and provide some suggestions for future research.