Abstract: The 4.5 mm thick Al-7.0Si-0.85Fe-0.30Mg recycled alloy plate was processed by friction stir for 1-3 passes with the same spindle rotation direction and for 2,3 passes by changing the second pass spindle rotation direction. The effect of spindle rotation direction on microstructure and mechanical properties of friction stir processing zone was studied. The results show that with increasing processing pass, the area of the processing zone and the width of the thermo-mechanical affected zone on the advancing side increased; the length of the second phase particles such as Fe-rich phase and eutectic silicon in the processing core area decreased, and the roundness increased; the strength and hardness had no significant change, and the percentage elongation after fracture significantly increased. After changing the second pass spindle rotation direction, the area of processing zone decreased compared with that with the same spindle rotation direction, but the microstructure symmetry was improved; the width of the thermo-mechanical affected zone on the advancing side decreased. After changing the spindle rotation direction, the second phase particle size did not change significantly, but the roundness decreased significantly; the strength and hardness did not change obviously, but the percentage elongation after fracture increased slightly.