This is an attempt to evaluate normal spleen size in the Koreans. Spleen scans were obtained in 29 patients who were admitted to the Seoul National University Hospital because of trivial illnesses. All scans were performed by use of $^{51}Cr$-labelled, heat-treated erythrocyte. As a simple screening criteria for the presence of splenomegaly, vertical height of the spleen was considered to be the best one. After statistical analysis it was concluded that the upper limit of normal spleen height is 13cm in anterior view and 14cm in lateral view.