Summary: The aim of this research is to compare two methods for erythorcyte sedimentation rate. The erytrochyte sedimentation rate is a test important in clinical practice and is used for monitoring the inflammatory state of the patient. The automated method on iSED analyzer was compared to the referenced Westergren method and the acceptability of the method was determined by statistical analysis. The Westergren method is a refrenced method for erythrocyte sedimentation rate. This method is performed using a Westergren pippete that is inserted in the test tube with anticoagulant sodium citrate (1:5) and after one hour the results are ready to be read. Analyzator iSED is an automated method that uses a whole blood sample in the tube with K3EDTA anticoagulant. It is a fast and simple method. In this research, 119 patient's blood samples, that were non clotted and non lipemic, were analyzed by both methods. Compatibility of methods was compared by statistical analysis using Bland Altman plot, Passing Bablok regression analysis and Spearman's coefficient of colleration. The two compared methods showed a good correlation however, systematic error, nonlinearity and deviations were observed, therefore it is concluded that the automated method on iSED analyzer can not replace the reference Westergren method