Simultaneous photodynamic therapy (PDT) and photothermal therapy (PTT) can reduce the risks of drug leakage, body burden, and preparation complexity in traditional combination PDT/PTT. Here, a versatile nanoporphyrin (Pp18‐lipos) self‐assembled from lipid–purpurin 18 conjugates (Pp18‐lipids) and pure lipids is presented. The as‐prepared Pp18‐lipos with 2 mol% Pp18‐lipids can perform effective PDT and fluorescence imaging. The Pp18‐lipos with 65 mol% Pp18 can perform potent PTT and photoacoustic imaging. The chelation of Mn2+ endows the Pp18‐lipids‐Mn2+ a high T1‐weighted magnetic resonance imaging contrast. Notably, pretreatment of low‐dose PDT facilitates the endocytosis and tumor accumulation of Pp18‐lipos, thus achieving synergistic PDT/PTT. Upon exposure to a single 705 nm‐laser, the combination of PDT/PTT achieves a significantly higher tumor growth inhibition rate than PDT or PTT alone. In addition, it is found that the synergistic PDT/PTT triggers more potent anti‐tumor immune response including tumor infiltration of immune cells and release of related cytokines.