A sthma is a disease in which many cells and cellular elements play a role, and isassociated with airway hyperresponsiveness manifested by recurrent episodes ofwheezing, shortness of breath, chest tightness and coughing, especially at night orin the early morning and is often reversible spontaneously or with treatment. Theimportant role of inflammatory cells, especially eosinophil cells in triggeringasthma symptoms. During a specific immune response, one of which is an asthmaresponse, there is an increase in the number of eosinophils in the blood. The purposeof this study was to determine the relationship between peripheral blood eosinophilvalues and the severity of asthma in asthma patients.METHODThis study used secondary data with a cross-sectional to 144 research subjects whomet the inclusion and exclusion criteria. Data collection was carried out by takingmedical record data at Adijdarmo Rangkasbitung Hospital from November toDecember 2022. Analysis was carried out using the Chi-square on the SPSS version26 program with a significance level of 0.05.RESULTSThere were 109 people (75.5%) had moderate-severe persistent asthma, 112 people(77.8%) had moderate-severe elevated peripheral blood eosinophil levels. Theresults of the Chi-square showed that there was a relationship between peripheralblood eosinophil values and the severity of asthma (p=0.000).CONCLUSIONThe results of this study showed that there was a significant relationship betweenperipheral blood eosinophil values and the severity of asthma.