Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is an important means of curing a wide range of hematologic diseases, and good hematopoietic and immune reconstitution after transplantation is one of the most important factors determining the success of the transplantation.Persistent thrombocytopenia after Allo-HSCT is one of the common post-transplantation complications.This is an investigator-initiated, single-center, single-arm, Phase II clinical trial to evaluate the efficacy and safety of Romiplostim N01 for platelet recovery after UCBT in patients with hematologic tumors. The study was conducted in patients ≥18 years of age with a diagnosis of hematological neoplasia who underwent UCBT. Subjects will be screened and receive roprostin N01 from +1 to +28 days after UCBT after signing an informed consent form, and the study will focus on the cumulative PLT implantation rate at 28 days after transplantation as the primary efficacy measure. The study is planned to enroll 34 patients.