3-CF3S substituted thioflavones and benzothiophenes were achieved via the reactions of AgSCF3 with methylthiolated alkynones and alkynylthioanisoles, respectively, promoted by persulfate. This protocol possesses good functional group tolerance and high yields. Mechanistic studies suggested that a classic two-step radical process was involved, which includes addition of CF3S radical to triple bond and cyclization with SMe moiety.