The immune and hematopoietic systems in the human body depend on the spleen. The understanding of anatomical and morphological variations of the spleen and its arterial vascular segments (AVS) is crucial for performing whole or partial splenectomy in the treatment of splenomegaly and splenic rupture. The aim of this study was to compare the anatomical differences in the spleen and its AVS in Thai cadavers of both sexes. This cadaveric study was performed on 77 cadaveric spleens (males = 38 and females = 39) from the Gross Anatomy Laboratory at the Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University. The average morphological measures of the observed spleens were 9.11±1.40 cm in length, 6.57±1.46 cm in width, 3.11±0.67 cm in thickness in male cadavers, and 8.77±1.87 cm in length, 5.91±1.35 cm in width, and 2.90±0.78 cm in thickness in female cadavers. The variations in spleen form were 7.79% oval, 16.88% tetrahedral, 28.57% triangular, and 46.75% wedge. The mean splenic hilum length was 5.14±1.10 cm in males and 5.12±1.22 cm in females. The mean lobar branch to hilum distance was 2.26±0.98 cm in males and 2.29±1.05 cm in females. Females were more likely than males to have two lobar arteries. Three lobar arteries, however, were more prevalent in males. The occurrence of accessory spleens was 2.63% for males and 7.50% for females. According to the data, there were significant differences in the number of lobar arteries and spleen size between male and female Thai cadavers.