Our aim was to defined the anthropometric profile of the Spanish rugby player and to studied the possible differences on morphologic characteristics between players. We analized the body composition, somatotype and proportionality on 31 senior players of National Rugby Team (age=26.1+/-3.8 years). For comparative purposes the sample was divided in two groups: fowards (n=19) and backs (n=12) as well as five groups: front row (8), second row (4), back row (7), half-back (4) and backs (wing, centre and full back) (8). The corporal density to estimate using the Jackson-Pollock (1978) and Durning-Womersley (1974) regression equations and for the muscular mass the methods described by Drinkwater-Ross (1980) and Martin et al. (1990). The Heath-Carter somatotype analysis were used. The proportionality were based on Phantom method (Ross and Wilson, 1974). Foward players are taller (p=<0.001), have higher body weight (p=<0.0001), and more arm span (p=<0.0002)-than Backs. The front row are the heviest and smallest; second row the tallest and biggest arm span, and back row are the lightest. Half-backs are lighter and smaller and with minor arm span than backs. Skinfolds values profile are statistically different, higher on forwards than backs, specially on medial calf and trunk measures between the five groups. Lean body mass (LBM) and fat percentage obtained is higher on forwards than backs (p=<0.01). The highier LBM was found on the second row and the lower on the half-backs players. The highier % fat was found on front row and the lower on backs. Muscular mass was higher specially on second row and front row. Mesomorphic were the dominant somatotype component as a part of endo-mesomorphy. Backs were on balanced mesomorphia. Proporcionality analysis showed: 'z' values lower than Phantom model with exception of trunk skinfolds of front row players. Body circumferences 'z' values are highier for upper extremity. Wrist and anterior-posterior chest depth have proportionality highier breadth values in contrast with hips wich are lower. Calf length 'z' values were positive for both groups. We may conclude that the anthropometric differences between the field positions are necessary to accomplish with the physical demands of specific play role. Among the scrum, front row needs high body weigth, both LBM and fat and high mesomorphysm, to oppose the other squad charge. Second row has similar LBM with less fat component but are the tallest and biggest and high arm span of all of groups, this characteristic gives them power, strength and more jump capacity, necessary for to getting balls. Third row have the lower fat percentage with high LBM, heigth and ectomorphysm necessary for getting balls and fast attacks. The backs have a similar body weight but different components, the backs have less fat weigth and more LBM than the half-backs and are less endomorphy making possible their capacity to run fast.