AbstractHypoxia, one of the representative characteristics in solid tumors, not only reduces the effectiveness of multiple treatments, but also relates to the tumor invasion and metastasis. Here, a hybrid core–shell nanoplatform to produce adequate oxygen, supporting for more effective tumor treatment, is developed. Composed of polydopamine cores, platinum nanoparticle interlayers, and zirconium‐porphyrin (PCN) shells, the hybrid core–shell nanoplatform works like a nanofactory, providing necessary products at different time and space. Platinum nanoparticle interlayers can catalyze the endogenous H2O2 to O2, which plays a dual rule in the enhanced tumor treatment. In the presence of light irradiation, O2 can be converted into the lethal reactive oxygen species by the PCN shell. In the absence of light irradiation, O2 ameliorates the hypoxic microenvironment, thereby reduces the invasion and metastasis of the tumor. Through a synergism of enhanced treatment and reduced metastasis, tumors could be treated more vigorously.