Colorectal adenocarcinoma (COAD) poses a serious threat to the life of the patient. Notably, Uroplakin 1 A (UPK1A) is a prognostic biomarker for a variety of tumors. However, the role played by UPK1A in the occurrence and development of COAD and its associated molecular mechanisms still lacks a clear and in-depth understanding. The relationship between UPK1A expression and clinicopathological features, as well as patient prognosis, was examined through the use of online databases. Differences in UPK1A expression in COAD tissues and adjacent normal tissues were assessed in clinical samples. The effects of knocking down UPK1A under Escherichia coli (E. coli) co-culture/non-co-culture conditions on COAD cell proliferation, cell invasion, and apoptosis were investigated. In vivo subcutaneous tumor xenograft model, we knocked down the UPK1A gene in a tumor mouse model and assessed tumor growth. The effects of UPK1A and E. coli on glycolysis were investigated by detecting mRNA expression of glucose consumption, lactate production, HIF-1α, and glycolytic enzymes (GLUT1, LDHA, and PDK1). UPK1A was highly expressed in COAD tissues and showed a positive association with unfavorable outcomes in colorectal cancer patients. By knocking down UPK1A, co-culture conditions with E. coli inhibited COAD cell proliferation and invasion, promoted apoptosis, and reduced tumor growth. Knockdown of UPK1A inhibited COAD cell glycolysis by modulating HIF-1α signaling under E. coli co-culture conditions. It is suggested that UPK1A and E. coli synergistically promoted COAD cell proliferation, invasion, and tumor growth and inhibited apoptosis. By regulating HIF-1α signaling, UPK1A and E. coli were able to promote glycolysis in COAD cells. UPK1A and E. coli synergistically interfered with junctional COAD processes.