Purpose: Spleen is enlarged in a variety of clinical conditions including infectious, infiltrative, immunologic and malignant states. Evaluation of splenic size is important in every physical examination of the abdomen by a physician. Determination of its size by palpation can be extremely inaccurate because spleen is never palpable till it is enlarged 2 to 3 times its own size. The accurate diagnosis of splenic enlargement is a matter of considerable importance as it is a useful guide for arriving at a diagnosis of the disease. It is therefore of utmost importance to resort to a mechanism that will give us an accurate estimation of the size of spleen. Aim of this work was to determine the normal range of spleen dimensions in average adult Saudi Arabian population and compare it from the published data. Methods: CT scans of 34 adult patients (male and female) aged between 20-70 years, having no splenic disorders, were collected from department of radio-diagnosis King Khalid Hospital Al?Kharj, KSA. Splenic volume was measured by two methods— by volumetric software and the prolate ellipsoid formula. Results: The average splenic volume of all subjects was 161.42 ±54.91 cm3 with a range of 106-319 cm3 . The average splenic volume of males was 196.95 ±48.70 cm3 and that of female was 196.95 ±26.97 cm3 . Conclusion: These results provide normative data for evaluating patients with splenic enlargement.