In this study, banana cellulose nanofibres (BNCFs) were prepared using waste banana stems. A novel two-dimensional (2D) Zn-MOF was synthesized using 5-(1-hydro-imidazolyl) isophthalic acid as the ligand. The results of the X-ray diffraction, thermogravimetry, and scanning electron microscopy analyses confirmed the stability of Zn-MOF. Thus, Zn-MOF was used to catalyze BNCFs grafted with poly(ε-caprolactone) (ε-CL) (BGCL) by homogeneous ring-opening polymerization in ionic liquid. The grafting ratio of the BGCL prepared by Zn-MOF reached 84.12 %, which was 10.03% higher than that catalyzed by 4-dimethylamino pyridine which was the state-of-the-art catalyst for this reaction. The banana cellulose nanofibres grafted with ε-CL reactions followed the coordination-insertion mechanism, which was confirmed by the theoretical calculations using the Materials Studio software. The cytotoxicity results indicated that BGCL was not only non-toxic to Hela cells but also promoted Hela cell growth within a certain concentration range. Therefore, this study demonstrated the promising potential of BGCL for biomedical applications, and the high efficiency, non-toxicity, and stability of Zn-MOF as the catalyst. Further, this will provide a theoretical basis for the application of MOFs as catalysts in polymerization reactions.