Cyclone separation device, dust collection assembly and dust collector

The invention provides a cyclone separation device, a dust collection assembly and a dust collector. The cyclone separation device comprises a first cyclone, a cyclone assembly and a filter part, wherein the first cyclone is provided with a longitudinal axis and an air inlet passage, the cyclone assembly comprises multiple second cyclones arranged on the upper portion of the first cyclone in the circumferential direction in parallel, a guided passage is limited between the two second cyclones, the guided passage guides the air to the periphery of the cyclone assembly along the peripheral wall tangent line of the adjacent second cyclone, each second cyclone is provided with an air-entraining notch to make airflow enter the second cyclones in the direction of the tangent line, the filter part is detachably arranged along the peripheral side of the cyclone assembly, the air on the periphery of the cyclone assembly enters the second cyclones through the filter part and the air-entraining notch in a tangent mode. According to the embodiment of the cyclone separation device, by means of the arrangement of the detachable filter part, in the process from a first cyclone separation space to a second cyclone separation space, purification is conducted on the airflow, and the filter part can be dissembled to make cleaning convenient.