The influence of comments is ignored in traditional rumor spreading models,however,it has recently become an important factor,especially with the wide and diversified application of comments in online social networks,such as bullet-screen,like button,and comment ranking.To address this,we propose an ICST rumor spreading model taking comment mechanism into account,which classifies the population involved in rumor spreading processes into ignorants (I),commentators (C),spreaders (S),and stiflers (T).The existence of the equilibriums is proved,based on which the sharp threshold of rumor propagation is given.Global stability of the information-elimination equilibrium and the information-prevailing equilibrium is proved by constructing Lyapunov function.Numerical examples are given to verify the above theoretical analysis.