Based on data of A+H dual-listed companies disclosing key audit matters in audit report in 2016 and 2017，this paper investigates whether the key audit matters supply consistent information and what factors affect the similarity by using text similarity calculation tool based on cosine algorithm. The research finds that the key audit matters disclosed in 2016 and 2017 have high text similarity，they cannot supply consistent information for now. Compared with the listed companies that have not changed auditor，the companies that have changed auditor have higher incremental information. When listed companies in different industries change their auditors，the information increment of key audit matters will increase to different degrees.