Nanocrystallization of organic molecular photosensitizers (PSs) by means of NMOF platforms has been demonstrated to be a promising approach to build up highly efficient PDT therapeutics. We report herein a new UiO-66 type of NMOF-based PS (UiO-66-TPP-SH), which is generated from UiO-66 NMOF and S-ethylthiol ester monosubstituted metal free porphyrin (TPP-SH) via a facile postsynthetic approach under mild conditions. The obtained NMOF (size less than 150 nm) with surface-decorated porphyrinic PS can not only retain MOF crystallinity, structural feature, and size, but also exhibit highly efficient singlet oxygen generation. Compared to the interior-located porphyrinic NMOF, UiO-66TPP-SH shows significantly higher photodynamic activity and more efficient PDT tumor treatment.