We observed that the tumor margin beyond effective PTT proliferated faster than the untreated tumor due to the upregulation of HSP, IDO, PD‐L1, etc. To efficiently inhibit the growth of the localized tumor and stimulate the host to generate an immune response to suppress the growth of the tumor margin beyond effective PTT and the distal tumor, we have developed a nanomedicine containing NIR photosensitizer (IR780) and IDO inhibitor (NLG919) to realize tumor photothermal therapy and immunotherapy. Here, IDO1 is linked to neoplasm.