The Sport Motivation Scale was developed in French and later translated into English and validated by Pelletier, et al. in 1995. It is based on the principles of self-determination theory. In this study the scale was translated into Spanish to assess and validate it for a sample of 275 athletes (78 women and 197 men) whose mean age was 21.3 yr. (SD=3.8) and who represented eight sports (track and field, tennis, swimming, waterpolo, soccer, basketball, handball, and volleyball). The Spanish version showed satisfactory internal consistency (Cronbach alpha of .70 to .80) and temporal stability (test-retest r = .69 to .74) over a 4-wk. period. A confirmatory factor analysis partially supported the seven-factor structure. Correlations among the subscales indicated a simplex pattern supporting the construct validity of the scale. Sex differences were found. Taken together, these findings support use of the Spanish version for assessment of motivation in sport.