In　industries　such　as　aerospace,　petrochemistry　and　automobile,　many　parts　of　different　machines　are　under　environment　which　shows　high　temperature　and　high　pressure,　and　have　their　proneness　to　wear　and　corrosion.　Therefore,　the　wear　resistibility　and　stability　under　high　temperature　need　to　be　further　improved.　Nowadays,　Laser　cladding　(LC)　is　widely　used　in　machine　parts　repairing　and　functional　coating　due　to　its　advantages　such　as　lower　dilution　rate,　small　heat-affected　zone　and　good　metallurgical　bonding　between　coating　and　substrate.　In　this　paper,　LC　is　introduced　in　detail　from　aspects　of　process　simulation,　monitoring　and　parameter　optimization.　At　the　same　time,　the　paper　gives　a　comprehensive　review　over　LC　material　system　as　high　entropy　alloys　(HEAs),　amorphous　alloy　and　single　crystal　alloy　have　been　gradually　showing　their　advantages　over　traditional　metal　materials　in　LC.　In　addition,　the　applications　of　LC　in　functional　coatings　and　in　maintenance　of　machine　parts　are　also　outlined.　Also,　the　existing　problems　and　the　development　trend　of　LC　is　discussed　then.　©　2021　Elsevier　Ltd