Abstract:Microblog (Weibo) ,as a newly rising social media ,has become a popular internet‐based communica‐tion platform since it is launched .By virtue of microblog ,netizens can instantly post short messages to de‐scribe ,update and share their current status ,presenting their attitudes toward certain events .Based on the an‐alytical framework of AFFECT‐JUDGEMENT‐APPRECIATION subsystem ,the present study attempts to in‐vestigate the attitudinal resources behind microblogs by analyzing the collected data of posts on Sina Weibo with topic“super smog in Harbin”as a context .The results suggest that :In event based Weibo posts ,users tend to express their attitude by employing affect‐judgement‐appreciation resources to achieve interpersonal meanings . This case study on the characteristics of attitude expression and linguistic resources in microblogging discourse may help interpret microblogging discourse and widen the application of appraisal theory .