As the most direct trade tool for regulating agricultural exports，institutional and policy arrangement of export tax rebate （ETR） has long been the basis for evaluating government support and encouragement of agricultural product exports， but whether the adjustment of ETR can meet the requirements of high-quality development in agricultural trade remains to be tested. Taking enterprises data from 2004 to 2013 as the sample，this paper investigated the impact of ETR on the scale and quality of export agricultural products by using instrumental variable and difference-in-differences model. The results show that the increase of ETR rate can improve the scale and quality of China’s export agricultural products， making it an effective policy measure for promoting high-quality development in agricultural trade. However，the impact of ETR on state-owned enterprises has the problem of ineffectiveness caused by the dual policy tilt. Moreover，the upward adjustment of ETR rate promotes the improvement of agricultural product quality through means such as reducing external market competition，optimizing internal resource allocation in enterprises，and increasing nvestment in innovation of R&D. Finally，the simulation experiment based on financial crisis reveal that the quality upgrading effect of ETR is still significant.