The invention belongs to the technical field of biological micro-fluidic chips, and provides a micro-fluidic device for gathering micro-nano biological particles through an oscillatory flow and a negative magnetophoresis effect. The micro-fluidic device is mainly composed of a micro-fluidic chip, a pressure system, a control system I, a control system II, a permanent magnet, a liquid storage pooland a guide pipe. According to the micro-fluidic device, efficient, convenient, fast and friendly gathering of the micro-nano biological particles can be achieved; and the micro-fluidic device for gathering the micro-nano biological particles is ingenious in design and easy to operate, 'infinite length channel' flowing is achieved in a short channel through the design of the oscillatory flow, negative magnetophoresis gathering and inertial gathering are organically combined, thus the rare micro-nano biological particles such as circulating tumor cells and exosomes can be efficiently gathered and enriched successfully, and the micro-fluidic device is applied to basic medical research and clinical detection.