Direct functionalization of inert C(sp3)-H bonds is a topic of immense contemporary interest and exceptional value in organic synthesis.The recent research has established a novel and practical protocol which features the engagement of vinyl cation species to functionalize C(sp3)-H bonds.The discussion of the topic is arranged by the strategies to generate the reactive intermediates,including ionization of vinyl triflates,addition of electrophiles to alkynes,tandem cyclization of enynes or diynes,and decomposition of β-hydroxy-a-diazo ketones.This review closes with a personal perspective on the dynamic research area of unactivated C(sp3)-H functionalization via vinyl cations.Hopefully,it will provide timely illumination and beneficial guidance for organic chemists who are interested in this area.Meanwhile continued development of the field is strongly anticipated in the