In summary, this study demonstrates, for the first time, that circ_0062682, a serum and serine deprivation-induced circRNA, promotes serine metabolism and tumor growth in CRC by regulating the miR-940/PHGDH axis, which not only helps to understand the detailed mechanism of cancer cells adapting to stress states, but also suggests that circ_0062682 is a potential novel therapeutic target for CRC. Here, PHGDH is linked to cancer.