Fe isotope geochemistry has been attracted more and more attentions recent years. Understanding the supergene processes occurred in the Earth surface system, which includes atmosphere, hydrosphere, biosphere, and the surface of lithosphere, are essential for geoscience. Here the Fe isotope compositions for soil, river, ocean and other main reservoirs of the Earth surface system and basic processes in Earth surface system leading Fe isotope fractionation were summarized. Fe isotope behavior during supergene processes including weathering, river transferring, sedimentation, diagenesis, and Fe cycling in ocean was also presented. The basic theory of Fe isotope geochemistry of Earth surface system have been constructed, and it shows that Fe isotope geochemistry is a powerful tracer for supergene geochemistry.