基于修订的第4版世界卫生组织（World Health Organization，WHO）造血淋巴肿瘤分类之后相关领域积累的研究成果和临床应用进展，WHO在2022年提出了第5版造血淋巴肿瘤分类（以下简称第5版分类）。第5版分类中骨髓增生异常性肿瘤/综合征（myelodysplastic neoplasms/syndrome，MDS）和急性髓系白血病（acute myeloid leukemia，AML）与第4版分类有较大更新，在临床实践中对疾病诊断和治疗，乃至疾病登记、科研等都具有重要意义。本文根据发表于Leukemia杂志出版的第5版分类和国际癌症研究机构官方网站上发布的第5版分类测试版进行解读。

In 2022, the World Health Organization (WHO) proposed the 5th edition of the WHO Classification of Haematolymphoid Tumours (referred to as the 5th ed. WHO classification) based on the accumulated research results and clinical application progress in related fields after the revised 4th Edition of the WHO classification. Myelodysplastic neoplasms/syndrome (MDS) and acute myeloid leukemia (AML) in the 5th ed. edition of the WHO classification. In practice in WHO classification has major changes from the revised 4th, it is of great significance for clinical disease diagnosis and treatment, as well as disease registration and scientific research. This article is interpreted based on the fifth edition of the classification published in the journal Leukemia and online ahead of print version on the official website of the International Agency for Research on Cancer.