Unhealthy dietary intake patterns and poor nutritional status in school students can have consequences on their health and academic performance. The aim of this study was to explore the dietary intake patterns and nutritional status of Omani school students and to determine their association with the student's academic performance. It was a cross- sectional study that included 203 Omani school students aged 12-15 years from grade 8th and 9th. A study questionnaire, Omani diet score and a semi-quantitative food frequency questionnaire were used to collect the data. The student's academic performance was measured by using the 1st semester Grade Point Average (GPA) of academic year 2018/2019. The results indicated that 36% and 22% of Omani school students consumed breakfast and all 3 meals regularly, respectively. Also 30.5% of students consumed fruits ≥ 2 serving/ day, 26.6% consumed vegetables ≥ 3 serving/ day and 48.8% consumed fish ≥ 2 serving/ week. Almost 31% of school students avoided sugar sweetened soft drinks and 26.6% of students tried to reduce fast food intake. According to body mass index for age (BMI-for-age); waist circumference (WC); waist-to-hip ratio (WHR) and waist-to- height ratio (WHtR), the obesity rates in school students were 26.1%, 31.5%, 27.6% and 31.5%, respectively. It was observed that both male and female school students did not have enough nutritional knowledge and their knowledge scores were 13.5 ± 16.9 for males and 28.8 ± 25.6 for females. The Omani diet score in both genders indicated unhealthy dietary intake patterns with 59.45 ± 8.39 for males and 58.4 ± 7.8 for females. The total daily energy intake (2227 ± 630 calories) in males was significantly higher than females (1617 ± 461). The results also indicated significant differences in male and female school students with regard to breakfast consumption, regular intake of all 3 meals, fruits intake, fish intake, avoiding soft drinks, nutritional knowledge and daily energy and macronutrients intake. Fish intake, avoiding soft drinks, WHtR and nutritional knowledge score showed significant associations with the student's academic performance. However, no significant association was found between the student's academic performance and breakfast consumption, regular intake of all 3 meals, fruits intake, reducing fast food, Omani diet score and daily energy as well as macronutrients intake. Overall the results indicated that healthy eating patterns and nutritional status are associated with better academic performance in school students. It is suggested that, the Ministry of Education, school managements and parents should focus more in developing healthy eating patterns in school students. Further research with larger cohorts is needed to validate these findings. Key words: Academic performance, dietary intake patterns, nutritional status, Omani school students.