With　the　large-scale　commercialization　of　5G　mobile　communication　systems　in　the　world,　6G　technology　is　becoming　a　new　hotspot　of　global　information　technology　research.　The　terahertz　band　(300GHz　to　3THz)　has　extremely　rich　frequency　resources,　which　can　support　ultra-high　speed　wireless　communication　from　100Gbps　to　1Tbps,　improve　the　existing　5G　peak　transmission　rate　by　one　or　two　orders　of　magnitude,　and　meet　the　requirements　of　new　applications　such　as　ultra-high　resolution　holographic　communication　and　meta-universe.　An　in-depth　understanding　of　the　propagation　channel　is　crucial　to　the　design　of　the　communication　system.　This　paper　summarizes　the　research　status　of　the　terahertz　channel,　including　its　characteristics　in　the　atmosphere,　the　current　channel　propagation　model,　and　terahertz　channel　measurement.　At　the　same　time,　the　future　research　direction　of　terahertz　communication　is　analyzed　and　prospected,　and　the　possible　challenges　in　the　future　research　are　discussed,　which　will　help　promote　the　application　of　terahertz　communication　technology　to　6G　communication.　Due　to　technical　limitations,　terahertz　channels　have　not　been　fully　developed　and　utilized　in　the　field　of　communication,　and　there　are　many　technical　bottlenecks　that　cannot　be　broken.　In　the　future,　new　channel　models　may　be　built,　and　there　will　be　opportunities　for　AI-assisted　channel　measurement.　©　2023　Institute　of　Physics　Publishing.　All　rights　reserved.