This　paper　presented　a　rapid　nitridation　route　to　fabricate　reaction-bonded　Si3N4/h-BN　ceramic　composite　by　the　addition　of　ZrO2.　The　effects　of　ZrO2　on　the　silicon　nitridation　behavior,　microstructure,　and　mechanical　properties　of　the　composite　were　investigated.　The　results　showed　that　ZrO2　could　effectively　promote　the　nitridation　of　silicon　and　significantly　influence　the　microstructure　and　mechanical　properties　of　the　composite.　The　best　nitridation　result,　almost　full　conversion,　was　achieved　when　the　ZrO2　content　was　8　wt.%,　and　the　outstanding　mechanical　properties　were　also　exhibited　at　this　condition.　TG-DTA　and　thermodynamic　analyses　revealed　that　the　inter-conversion　between　ZrO2　catalyst　and　ZrN　metastable　phase　could　effectively　inhibit　microzone　melting　of　silicon　and　make　the　fresh　surfaces　of　silicon　particles　exposed　to　nitrogen,　and　consequently　accelerated　the　nitridation　of　silicon.