Herein, we evaluated the information published in The Cancer Genome Atlas (TCGA) database and performed quantitative PCR (qPCR), western-blot, and immunohistochemistry (IHC) staining; our results revealed that CTSG was substantially decreased in CRC tissues, and subjects with CTSG low-expression had poorer overall survival. The gene discussed is CTSG; the disease is colorectal carcinoma.