By using the financial data of China's A-share listed companies and Hexun's social responsibility scores from 2010 to 2021, the paper explores the impact and its channels of corporate social responsibility(CSR) on investment efficiency, which turns out that it can be improved by CSR by strengthening internal governance. Further, CSR can enhance both industrial and financial investment efficiency. This finding provides a useful reference for China's microeconomic entities to actively fulfill CSR and improve investment efficiency.