Organic photocatalysis has garnered significant interest in the field of photochemistry because of its ability to generate active radical species under mild conditions via energy or electron transfer from the excited state of photosensitizers to organic molecules. Quinolinones and coumarins are privileged scaffolds that are widely distributed in natural products and pharmaceutical agents. Recently, quinolinones and coumarins have emerged as promising organic photosensitizers for a variety of chemical transformations. Significant advances in the development of synthetic methods via organic photocatalysis have elucidated their essential electronic properties, leading to the development of highly site-selective synthetic methods. This mini-review highlights recent innovative approaches to site-selective C-H bond functionalization catalyzed by light-absorbing quinolinone and coumarin scaffolds.