Based on comprehensive analysis of geological data，well logging and seismic interpretation，the main carrier systems（including sand bodies and faults）in the Yanchang Formation in Honghe oilfield were studied，and the characteristics of carrier systems and their important effect on hydrocarbon accumulation were analyzed. By the method of basin simulation，the palaeodynamics generated at the key period of hydrocarbon reservoiring were recovered in this area. The results obtained show that the reservoirs of Chang8 member in Yanchang Formation were situated in an overpressured system during the key reservoiring period，and the overpressure became the main driving force for hydrocarbon migration. Based on the analysis of petroleum migration mechanism and migration and accumulation regularities in Chang8 member，it is determined that the carrier system is composed of effectively connected active faults and carrier beds，which makes a composite fault-fracture-sand carrier system. Oil and gas migrates along the direction of pressure drop and entrapped in effective low potential zone. The next favorable exploration targets are lithologic and structural-lithologic traps with better lateral sealing conditions or physical property“sweet point”and effective low potential.