Based on the company’s disclosure of key customer information, the impact of corporate customer concentration on analyst forecast was studied, and we further studied the impact of detailed customer names on analyst forecasts. It is found that: (i) customer concentration significantly affects the accuracy of analyst forecasts. The higher the customer concentration is, the lower the accuracy of analyst forecasts is; (ii) Voluntary disclosure of customer names can provide incremental information to analysts and mitigate the negative impact of customer concentration on the accuracy of analyst forests; (iii) further research has found that the incremental information brought by the state-owned enterprises’ disclosure of the customer names to analysts is more obvious; disclosure of customer names by companies with high environmental uncertainty is more likely to be of concern to analysts; and star analysts have a higher ability to interpret customer names than non-star analysts.