A UiO-66 core with various sizes acts as heterogeneous nucleation center and enables aniline polymerization under ambient conditions. The as-synthesized UiO-66@PAN possesses uniform size and excellent dispersibility in aqueous solution. UiO-66@PAN can be internalized by cancer cells via endocytosis, and indicates signifi cant photothermal therapeutic effect in vitro, and can effectively inhibit the growth of colon cancers in vivo.