Abstract: Eosinophil disorders are a range of heterogeneous diseases, which manifest as persistent increase of eosinophile granulocyte in blood and tissue, and may cause microenvironment change and irreversible chronic organ damage. According to World Health Organization, eosinophil diseases were divided into hypereosinophilia (HE) and hypereosinophilia syndrome (HES) by whether the organ is involved. Besides familial HE, HE were also divided into secondary (reactive) HE, primary (clonal/ neoplastic) HE, and idiopathic HE. Lymphocytic variant HE is a special kind of secondary HE. With the study of the molecular mechanism of lymphocytic variant HE, the diagnosis is gradually clear. Moreover, some targeted therapeutic drugs, such as anti IL-5 monoclonal antibody (Mepolizumab) and anti CD52 monoclonal antibody (Alemtuzumab) were also appeared. In this paper, the current basic and clinical researches of lymphocytic variant HE are reviewed.