The invention relates to an oil production system and oil production method based on nano-magnetic fluid. The oil production system based on the nano-magnetic fluid comprises an injected water container, a magnetic fluid container, a displacing fluid container, a high-pressure pump unit and an electromagnet; water and the nano-magnetic fluid are mixed to be uniform in the displacing fluid container, an obtained mixture enters the high-pressure pump unit through a first displacing fluid delivery pipeline to be pressurized, and then the pressurized mixture enters a water injection well through a second displacing fluid delivery pipeline. According to the oil production system and oil production method based on the nano-magnetic fluid, the displacing front edge is monitored along with the displacing process, the oil displacing direction and speed are adjusted through the strong attraction force of a magnetic field on the displacing fluid in a low-wave and regional newly-drilled magnetic source well, remaining oil is effectively utilized, and the displacing efficiency is improved. Compared with a traditional new well drilling and injection-production pattern improving method, the oil production method has the advantages of being low in cost and high in controllability.