In this communication, we describe an inexpensive and feasible method for the preparation of hexagonal boron nitride (h-BN) nanorods in the absence of metal catalyst. Tertiary calcium phosphate (Ca-3(PO4)(2)) and ammonium biborate hydrate (NH4HB4O7.3H(2)O) were selected as starting materials where calcium phosphate was used as a diluting agent to prevent the formation of bulk B2O3 during the thermolysis of ammonium biborate hydrate. The mixture was nitrided at 900degreesC in the flowing ammonia and was transformed into h-BN nanorods after subsequent crystallization. After crystallization at 1650degreesC for 2 h, the unique microstructure of h-BN nanorods was observed.