The work aims to solve the problems of collision damage and blind sector in magnetic needle magnetic grinding process. Magnetic abrasive particles were added to increase the flexibility of the magnetic needles. At the same time, the magnetic needle provided grinding pressure and cutting force for the magnetic abrasive particles. The three-phase sinusoidal alternating current was connected to the stator coil, and the phase difference of the alternating current was used to generate a rotating magnetic field to drive the mixed abrasive to grind the tiny and complicated workpieces. Under the condition that the total mass of the mixed abrasive was unchanged, the magnetic needles, the magnetic abrasive particles and the mixed abrasive with different mass mixing ratios were sequentially used to carry out comparative experiments. Compared with single abrasive, the workpiece surface morphology after 40 min of processing with mixed abrasive was better. The surface roughness value decreased greatly, and there was a larger amount of material removed. When the mass mixing ratio of the magnetic needle and the magnetic abrasive particles was 1∶2, the surface morphology of the processed workpiece was the best, and there was no obvious processing texture or magnetic needle collision trace. The surface roughness of the workpiece decreased from the original Ra 1.0 μm to Ra 0.54 μm. The material removal amount was about 2.8 mg. There was no grinding dead angle in the micro groove. In the electromagnetic grinding process, the use of a mixed abrasive of magnetic needles and magnetic abrasive particles with a mass mixing ratio of 1∶2 can improve the grinding effect and prevent the surface of the workpiece from being damaged by the collision of the magnetic needles. The magnetic needle can squeeze magnetic abrasive particles into narrow grooves of the workpiece without grinding blind areas.