Background A novel nanoemulsion (CU/FU-LN) was developed as an oral 5-fluorouracil and curcumin co-delivery system for synergistic efficacy against liver cancer.Methods MTT assay, confocal laser scanning microscope, and H&E staining were utilized to establish the efficacy and safety of CU/FU-LN.Results The AUC(0-t) of CU/FU-LN was 8.85-fold and 8.59-fold greater than those of CU and FU, respectively. The IC50 of CU/FU-LN was 4.6-fold and 4.9-fold lower than those of FU and CU in HepG2 cells, respectively. In vivo anti-tumor trials, the tumor inhibition rate was significantly elevated by CU/FU-LN (49.29%), compared 24.84% and 4.72% for FU and CU, respectively. Ki-67 immunohistochemical analysis revealed that CU/FU-LN had an obvious anti-proliferation effect. The IC50 of CU/FU-LN in L02 cells was 1.51-fold and 2.60-fold higher than those of CU and FU, respectively. Certain vital organs in the mice of the CU/FU-LN group showed markedly fewer lesions than those of the CU, FU, and CU+FU groups. The CU/FU-LN treatment caused no significant change in mouse body weight relative to the control group (P > 0.05). Conclusions We successfully prepared a promising co-delivery platform for the synergistic treatment of liver cancer and it has a comparatively enhanced efficacy and mitigated toxicity.