With non-financial listed companies in Shenzhen A-share stock market from 2014 to 2017 as research sample, a study has been made of the relationship among heterogeneity of institutional investors, nature of property rights and accounting information quality. It is found that institutional investors’shareholding contributes to the improvement of accounting information quality, but it is limited in state-owned holding companies, which has been better reflected in non-state-owned holding companies. Based on these findings, a further exploration has been made of the heterogeneity of institutional investors in non-state-owned holding companies (under pressure-resistant and pressure-sensitive categories). The results show that, compared with pressure-sensitive institutional investors, pressure-resistant institutional investors play a more positive role in the improvement of accounting information quality.