Background: Thrombocytopenia after allogeneic hematopoietic cell transplantation is a challenging clinical problem. Recombinant human thrombopoietin (rhTPO) and thrombopoietin receptor agonists are increasingly used in posttransplant thrombocytopenia. However, the use of hetrombopag in patients with posttransplant thrombocytopenia, especially in patients with resistance to rhTPO, has not yet been reported. Objectives: The present study aimed to investigate the efficacy and safety of hetrombopag in patients with rhTPO-resistant posttransplant thrombocytopenia. Methods: This retrospective study included 21 patients with rhTPO-resistant post- transplant thrombocytopenia who received hetrombopag from August 2021 to July 2022. The primary endpoint was the overall response rate, including partial response and complete response (CR). We also evaluated the predictors of hetrombopag efficacy and adverse events. Results: The overall response rate to hetrombopag was 81%, and the CR rate was 62%. The median time from hetrombopag initiation to response and CR were 16 and 31 days, respectively. Decreased megakaryocytes in bone marrow negatively correlated with CR to hetrombopag (P = .03). All the patients tolerated hetrombopag well without any significant increase in adverse events. At the last follow-up, 71% of responders had discontinued hetrombopag and sustained their best response. Conclusion: Our results suggested that hetrombopag is an effective treatment option to promote platelet recovery in patients with posttransplant thrombocytopenia, even in patients resistant to rhTPO.