An oil mist recovery, separation and purification device for a minimum quantity lubricant (MQL) grinding process, including: a pneumatic separation mechanism, a pipeline and a fan fixedly connected with one end of the pipeline, wherein the fan is configured to form a negative pressure in the pipeline, one cone-shaped filter mesh mechanism is disposed in the pipeline, and a tip of the cone-shaped filter mesh mechanism faces the side of an air inlet direction of the pipeline; and a filtering and recovery mechanism connected with the pipeline and including a case body, a filtering mechanism and a recovery mechanism, wherein the case body is connected with the pipeline through a connecting part, and the filtering mechanism is connected with the recovery mechanism. The device can separate, recover and reuse oil mist particles in the air.