Based on Genre Theory and Appraisal Theory within the framework of systemic functional linguistics, this article aims to investigate the generic structure in company public apology letters written in Chinese as well as their semantic features,especially in terms of evaluative meaning.This study shows that the generic structure of this type of letters determined by its contextual configuration presents a certain degree of regularity.Besides,evaluative meaning of different types is unevenly distributed throughout the letter and different structural element manifest different type of evaluative meaning.These language features fully reflect the companies' communicative purpose,which is to obtain forgiveness from consumers and persuade consumers to continue using their products and services.As for the hot phenomenon that many companies issue public apology letters on Weibo,the reason lies in the improvement of consumption environment in China.