As industrialization accelerates, the pollution problem of Zn2+ is becoming increasingly severe, posing a significant threat to the stability of ecosystems and engineering structures. To cope with this challenge, this paper studies the solidification effect of MICP (Microbially Induced Carbonate Precipitation) combined with magnesium oxide on Zn2+ contaminated red clay. The variation of unconfined compressive strength and shear strength index of solidified soil under different concentrations of cementation solution, magnesium oxide contents and Zn2+ concentrations was discussed by unconfined compressive strength test and direct shear test. The curing effect of MICP combined with magnesium oxide technology on Zn2+ was analyzed by ion occurrence form test and pH value change of samples before and after curing. The results show that the incorporation of magnesium oxide significantly improves the unconfined compressive strength and shear strength of Zn2+ contaminated red clay. When the content of magnesium oxide is 5%, the utilization rate is the highest. When the concentration of cementation solution is 1.0 mol/L, the unconfined compressive strength and shear strength are the highest. The shear strength index of solidified samples is mainly affected by the content of magnesium oxide. The incorporation of magnesium oxide facilitated calcium carbonate precipitation during MICP by elevating the pH value. This process accelerated the transformation of zinc ions from a weak acid-extractable state to reducible, oxidizable, and residual states. Therefore, the combined MICP and magnesium oxide solidification of Zn2+ contaminated red clay holds promising applications and can provide guidance for the remediation of polluted site foundations.