Diatomite　is　an　inorganic　nonmetallic　mineral　material.　Due　to　unique　ordered　pore　structures,　applications　of　diatomite　have　been　realized　in　chemical　engineering　and　building　materials　industries.　The　application　of　diatomite　was　usually　limited　by　its　specific　surface　area　(about　18-28　m2/g).　Through　the　functionalization,　diatomite　materials　could　be　vested　with　a　certain　property,　thus　improving　the　performance　in　environment　treatment　and　advancing　applications　in　the　field　of　energy　and　bioengineering.　Therefore,　functionalization　of　diatomite　has　become　a　research　focus.　In　recent　years,　researches　on　functionalization　of　diatomite　mainly　focus　on　three　areas:　noncovalent　functionalization,　covalent　functionalization　and　chemical　conversion　of　diatomite.　Normally,　noncovalent　functionalization　indicate　that　using　nano　metal　oxides　and　metal　oxygenates　to　modify　diatomite　and　the　functionalized　diatomite　can　be　used　in　the　field　of　energy,　water　treatment　and　sensors.　Covalent　functionalization　of　diatomite　refers　to　modifying　diatomite　with　functional　monomer　through　the　connection　of　Si-O　covalent　bond　based　on　Si-O　tetrahedron　and　Si-OH　of　diatomite.　Functional　monomers　are　classified　into　silicates　and　silane　coupling　agents.　Silane　coupling　agents　connect　to　diatomite　through　Si-OH,　and　it　could　also　be　used　to　connect　other　functional　groups　to　obtain　excellent　properties.　Covalent　functionalized　diatomite　is　commonly　used　in　the　fields　of　energy,　sensor　and　water　treatment.　The　chemical　conversion　of　diatomite　to　silicon　source　is　the　other　functionalization　met-hod.　Silicon　keeps　the　morphology　of　diatomite　and　can　be　used　in　the　field　of　energy　and　bioengineering.　Functionalization　of　diatomite　is　the　key　to　realize　the　application　of　diatomite　materials　in　emerging　fields.　Therefore,　researches　on　diatomite　functionalization　would　advance　the　application　of　diatomite　and　promote　the　development　of　emerging　areas.　Here,　the　progress　of　diatomite　functionalization　at　home　and　abroad　in　recent　years　are　summarized.　The　functionalization　routes　and　their　applications　are　introduced　in　detail　in　order　to　provide　reference　for　advanced　diatomite　functionalization　routes　and　their　applications.　©　2020,　Materials　Review　Magazine.　All　right　reserved.