Titanium　alloys　have　been　known　as　useful　materials　for　their　superior　mechanical　properties,　low　density　and　high　specific　strength.　However,　the　application　of　conventional　titanium　alloys　on　engine　parts　of　airplane　is　limited　by　their　poor　wear　resistance,　low　fatigue　strength　and　low　hardness.　Particles　reinforced　titanium　matrix　composites　have　attracted　extensive　investigation　in　material　science　and　engineering.　Mechanical　properties　can　be　improved　by　reinforcing　the　loaded　outer　layer　of　Ti　with　ceramic　particles.　TiB　and　TiB2　are　considered　as　the　excellent　ceramic　reinforced　particles　for　their　compatible　physical　and　thermodynamic　properties,　high　hardness　and　Young＇s　modulus　of　elasticity.　However,　TiB2　has　high　brittleness.　The　intermetallic　compound　NiTi,　wellknown　for　its　shape　memory　effect　and　pseudo-elasticity,　is　one　of　the　rarely　few　intermetallic　compounds　having　excellent　combination　of　high　strength,　ductility　and　toughness　as　well　as　excellent　wear　resistance　and　fabrication　processing　properties.　An　in　situ　TiB/TiB2　structured　ceramic　materials　as　the　reinforcing　phase　and　NiTi　intermetallic　phase　as　the　matrix　would　be　expected　to　have　an　outstanding　combination　of　high　hardness　and　toughness.　To　investigate　the　microstructure　and　properties　of　the　cladded　layers,　two　types　of　composites　were　prepared　by　laser　cladding　powders　containing　TiB2　and　Ni+TiB2　as　a　preset　level　on　the　surface　of　titanium　alloy.　The　composite　coatings　were　analyzed　by　XRD,　SEM,　EPMA,　micro　hardness　tester　and　brinell　hardness.　The　results　showed　that　TiB2　particulate　and　TiB　short　fiber　reinforced　titanium　matrix　composite　coating　were　obtained,　which　had　poor　quality　of　coating　shape　when　Ni　was　not　added.　The　coating　was　mainly　composed　of　TiB2,　TiB,　Ti　and　NiTi　phase　when　Ni　was　added　and　surface　coating　quality　was　improved　and　the　bcc　structure　of　NiTi　alloy　was　filled　with　TiB2　particulate　and　TiB　short　fiber　surrounding.　The　coating　was　coarse　with　particle　size　of　TiB2　at　3　similar　to　5　mu　m　when　Ni　was　not　added,　while　it　contained　fine　particles　of　TiB2　with　particle　size　of　0.5　similar　to　3　mu　m　and　beta-Ti　base　appeared　when.　Ni　was　added.　The　micro-hardness　of　the　coating　was　reduced　when　Ni　was　added,　but　the　fracture　toughness　of　the　coating　increased.　The　mechanism　of　toughening　was　discussed　based　on　fracture　behaviors.　Fracture　toughness　of　titanium　matrix　composite　coatings　were　improved　mainly　through　particle　debonding　and　short　fiber　breakage　by　the　offset　resulting　in　crack　deflection.