The high-temperature tribological behavior of the h-BN/Al2O3 self-lubricating composite ceramics demonstrated a temperature-dependent variation, with an ultra-low friction coefficient about 0.09 being achieved at 1000 ◦C in an air environment when countered with Si3N4 pins. The molten B2O3 phase can effectively accumulate and mix the free h-BN phase at the friction interface to form a high-temperature adaptive similar solid-liquid tribo-film, thus providing ultra-low friction coefficients for composites in high-temperatures air environments. Meanwhile, the in-situ generated Al5BO9 phase can efficaciously enhance the strength and wear resistance of the friction interface, furnish mechanical support for the solid lubrication layer and preserve its structural integrity and stability during high-temperature friction.