Recent data have indicated that universities in the United States (U.S.) host as many as 21,933 students from Saudi Arabia, making Saudi Arabia one of the top four countries for international students attending U.S. universities. Several research studies have indicated that religiosity and acculturation influence student's performance. However, there is a scarcity of studies that assessed the relationships among acculturation, religious practices, and the academic performances among Saudi Arabian students in the U.S. The purpose of this study was to examine the relationship among acculturation, religiosity, and academic performance among Saudi Arabian students in the United States. This study was a cross- sectional quantitative survey design with a sample of 393 Saudi students enrolled in U.S. universities. Islamic religious practices and beliefs were measured by the Religiosity of Islam Scale, whereas acculturation was measured by the Vancouver Index of Acculturation. The findings of this study indicate that the overall mean GPA was 3.56, and female students had significantly higher overall GPA than male students. The results show that there was a statistically significant, weak positive relationship between religious practices and academic performance, and a significant, weak negative relationships between acculturation heritage and religious practices and beliefs. The study findings also indicate that religious practice and gender were significant predictor of academic performance. Other factors, such as religious beliefs and acculturation were not predictors of academic performance. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]