ESG ratings are an important reference basis for analysts’ earnings forecasts, yet there is a wide divergence in the rating information provided by different rating agencies. Based on this, this paper empirically examines the impact of ESG rating divergence on the accuracy of analysts’ earnings forecasts using a sample of A-share listed companies in the Chinese capital market from 2009 to 2021. The research shows that: (1) ESG rating divergence significantly reduces analysts’ earnings forecast accuracy. (2) Mechanism test shows that ESG rating divergence has a negative impact on earnings forecast accuracy by increasing the information processing cost of analysts. (3) Heterogeneity analysis shows that economic policy uncertainty will exacerbate the negative impact of ESG rating divergence on the accuracy of analysts’ earnings forecasts, while good internal control can mitigate the negative impact of ESG rating divergence on the accuracy of analysts’ earnings forecasts. (4) The economic consequences test reveals that the dampening effect of ESG rating divergence on the accuracy of analysts’ earnings forecasts exacerbates corporate finance constraints. The findings contribute to a deeper understanding of the informational value and economic consequences of ESG rating divergence, while enriching the literature on the factors influencing the quality of analysts’ earnings forecasts.