Background: One of the most common tests performed in the hematology laboratories is erythrocyte sedimentation rate (ESR) that for monitoring infections, inflammatory and cancers diseases. The aim of this study was investigation of ESR in patients referred to Golestan hospital, Ahvaz.Methods: This descriptive and cross-sectional study was done in second half of 1388 on outpatient and hospitalized in different wards of the Golestan hospital, Ahvaz, and ESR was tested by Westergrene method. Data were analyzed by SPSS and using T test.Results: In the present study, mean of Erythrocyte Sedimentation Rate was in males and female, 34.5±12.5 and 33.9±12 respectively , that this difference was not statistically significant (P>0.05), mean of age was in males and female, 28.1±13, and 26.9±12.1 respectively, the difference was not statistically significant (P>0.05). There were 51 % males and 49% female.38%of patients in outpatient and 62% in different wards of, the Golestan Hospital, were hospitalized.Conclusion: The results of present study demonstrated increased of ESR in male and female almost identical. ESR was increased more among hospitalized patients than in the outpatient, that probably due to factors such as inflammation, infections, malignancies, autoimmune diseases and ... in hospitalized patients.