Abstract: Manganese-based metal organic frameworks (MOF) materials have attracted much attention from researchers due to their high visible light response and high photogenerated carrier transfer efficiency, but their high photogenerated carrier complexation rate limit their application in photocatalysis. The MOF-on-MOF structure not only promotes the charge separation and carrier transfer efficiently, but also better enlarges the surface area and porosity. The Z-type heterojunction catalyst NH₂-MIL-88B (Fe)-on-MOF-74-Mn was successfully prepared by a hydrothermal method, and its degradation rate of tetracycline reached 93%, which was 2.9 times higher than that of the pure sample of MOF-74-Mn, and 1.7 times higher than that of the composite material NH₂-MIL-88B (Fe), after irradiation with visible light for 60 min. The results show that the MOF-on-MOF structure increases the specific surface area of a single MOF material to provide more active sites, while the Z-type heterojunction inhibits the complexation of photogenerated electrons and holes, thus improving the carrier separation efficiency, and enhancing the performance of the photocatalysts with the combined effect of both. This study is expected to provide strong support for solving the practical application problems of photocatalysis and promote its better role in the field of degrading organic pollutants.