Abstract: The distribution characteristics of distributive fluvial system can help accurately predict the location of favorable reservoir.Typical branch channels are developed in the Huangshuigou alluvial fan and the Qingshuihe fan delta plain at the northern margin of Bosten lake in Yanqi Basin of Xinjiang, thus forming a distributive fluvial system. Based on detailed observations of sedimentary outcrops and field surveys, the sedimentary characteristics and controlling factors for braided channels of the distributive fluvid system in the Huangshuigou alluvial fan and the Qingshuihe fan delta plain are analyzed from "source" to "sink". The Huangshuigou alluvial fan is divided into three zones, and the Qingshuihe fan delta plain is divided into four zones. The variation of sedimentary characteristics in different zones is mainly manifested by the decrease of sediment unloading and hydrodynamic force, the decreasing particle size with the increasing of transport distance, and the narrowing of river channel. The distributive fluvial system shows a larger sedimentary range than a single channel phase, presenting certain advantages in favorable reservoir prediction. Under the same conditions of current arid climate and tectonic setting, the supply of provenance, unloading of rivers, sediment diffusion, and slope of the fan are the main factors controlling the sedimentation differences between alluvial fans and fan delta distributive fluvial systems.