AbstractCombination therapy is considered to be an effective strategy for enhanced tumor treatment. Here we fabricated amorphous dual metal (FeMn)‐porphyrin based coordination polymer nanoparticles FeMn‐TCPP NPs via a facile and mild protocol. The formed FeMn‐TCPP NPs possessed the combination therapy between photodynamic therapy attributed to TCPP ligand and chemodynamic therapy mainly ascribed to chemodynamic therapy agent Fe (II). Moreover, Mn (II) as a T1 contrast agent endowed the FeMn‐TCPP NPs with significant r1 relaxivity for MRI imaging. Notably, FeMn‐TCPP NPs not only integrated the functional agents into one nanoplatform but also exhibited synergetic effects for enhanced combination therapy. All the features allowed the FeMn‐TCPP NPs as an all‐in‐one nanoplatform toward precision cancer therapy.