Co-based catalysts have gained significant attention in recent years due to their excellent ability to activate C-H bonds and high selectivity towards olefins, despite being a non-noble and environmentally unfriendly metal. However, further improvements are necessary for practical utilization, particularly in terms of activity and anti-carbon deposition capacity. In this study, we synthesized Al2O3 nanorods with abundant pentacoordinated Al3+ (Al3+penta) sites. The supported Co on the Al2O3 nanorod (Co/Al2O3-NR) exhibited higher selectivity (>96% propylene selectivity) and stability (deactivation rate 0.15 h-1), compared to Co supported on an Al2O3 nanosheet with fewer pentacoordinated Al3+ sites. Various characterizations confirmed that Co(II) mainly exists as CoAl2O4 rather than Co3O4 in the form of Co/Al2O3-NR, which inhibits the reduction of Co(II) to Co0 and improves catalyst stability accordingly.