This study aims to identify the relationship between the big five personality traits and academic perseverance among the 12th grade students in Muscat Governorate in the Sultanate of Oman. Also, it aims to identify the level of academic perseverance of the 12th grade students in Muscat Governorate in the Sultanate of Oman. Also, the study aims to search for statistically significant differences in the five traits among a sample of 12the grade students in Muscat Governorate attributable to the study variables (gender, course type (applied or pure science). In addition, it aims to search for statistically significant differences in the level of academic perseverance on a sample of 12th grade students in Muscat Governorate attributable to the study variables (gender, course type (applied or pure science). The researcher uses a descriptive correlational method. The sample consists of 439 students (137 male) and (302 female). The researcher uses the five traits scale by Costa and McCrae (Al Kalbani arabization, 2006) and the academic perseverance scale (Dhunaibat, 2018). The study shows the following results: openness to experience ranked first as the most prominent factor among the study sample, followed by extraversion, conscientiousness, and agreeableness respectively. The results also show a high level of academic perseverance among the sample. Also, a statistically significant positive correlation is found between openness to experience, extraversion, conscientiousness, agreeableness, and academic perseverance. In addition, there is a negative non-statistically significant relationship between neuroticism and academic perseverance. The results show statistically significant differences in neuroticism dimension in favour of the female students. Moreover, there are statistically significant differences attributed to the course variable in the openness to experience dimension in favor of the applied course. Also, the results show no statistically significant differences attributed to the course variable in all the dimensions of the academic perseverance. There are no statistically significant differences attributed to the gender variable in the dimensions of the academic perseverance (challenge preference, desire for mastery, and curiosity) except tolerance and patience dimension in favor of the female.