Colorectal cancer (CRC) is the most common malignancy of the gastrointestinal, however, the underlying mechanisms of CRC remain largely unknown. New evidence suggests that the PI3K/AKT/mTOR pathway is closely related to CRC. PI3K/AKT/mTOR is a classical signaling pathway that is involved in a variety of biological processes, such as regulating cellular metabolism, autophagy, cell cycle progression, cell proliferation, apoptosis, and metastasis. Therefore, it plays a crucial role in the occurrence and development of CRC. In this review, we focus on the role of the PI3K/AKT/mTOR pathway in CRC, and its application of to the treatment of CRC. We review the importance of the PI3K/AKT/mTOR signaling pathway in tumorigenesis, proliferation and progression, and pre-clinical and clinical experience with several PI3K/AKT/mTOR pathway inhibitors in CRC.