An efficient metal-organic framework catalyst was developed with manganese tetrakis(4-carboxyphenyl)porphyrin as either bridging moiety or catalytically active sites under a hydrothermal condition. Surprisingly, the X-ray diffraction details showed that this porous network, MMPF (MMPF denotes iron-connected metal metalloporphyrinic framework) was successfully constructed with a physically flexible framework and resistance to basic solution. Accordingly, catalytic studies have demonstrated that MMPF can catalyze the selective oxidation of a variety of substrates with PhIO as oxidant in acetonitrile solution under mild temperature. More importantly, the MMPF outperformed the homogeneous Mn-TPP in catalyzing epoxidation of cyclohexene, mainly due to its high efficiency of 3D network-based nanochannel-reactor in MMPF. This gave rise to a structural resistance to formation of catalytically inactive species.