Introduction: Spiritual intelligence (SI) by integration of internal values with the external environment solves our problems of meaning and value and may be associated with achievement motivation . This study was carried out to investigate the relationship between SI with achievement motivation and academic success of students .   Materials and Methods: 285 students of Fasa University of Medical Sciences were randomly selected for this cross-sectional study. They filled the demographic questionnaire of Badie Spiritual intelligence and Herman’s achievement motivation. Having an average grade mark of 15 out of 20 and not having failed in any subjects at any time during their courses of study were the criteria for the educational achievement in this study. Ranges of spiritual intelligence scores were 42-210 and for Achievement Motivation was 29-116 respectively. Chi-square, t- test, ANOVA and Pearson correlation were used for comparing the groups.   Results: 83% of the students were considered among the successful groups and in comparison to the unsuccessful students had higher spiritual intelligence scores but this difference was not statistically significant 152.6±16.8 vs. 148.8±18.2. Grade point average and last semester's grade point average had a positive and significant relationship with self-consciousness and overall self beliefe (p