Background Nutritional intake plays an important role in determining energy availability which is vital to health, wellbeing, and sports performance in an active population. This research assessed the sports undergraduates' nutritional intake compared to the Dietary Guidelines for Americans and nutrition goals provided by WHO. Methods This study is a quantitative, cross-sectional descriptive study. One hundred and one (n = 101) sports undergraduates aged between 20 to 23 years were recruited and the nutrient intake was assessed using the three-day food diary method and quantified the macro and micronutrients by the food composition database. One sample t-test was performed to compare the mean nutrient intakes with the lowest recommendation values. Results Though most undergraduates were able to meet the dietary requirements in carbohydrates, they were deficient in their protein intake and exceeded in fats intake. Further, both male and female students were deficient in their daily energy intake (1723 kcal, 1607 kcal) and dietary fiber intake (8 g, 11 g). The saturated fat intake was met by all students while 20% of males and 21% of females exceeded the recommendations (< 10%). The micronutrient intake of vitamins such as C, B1, B2, B9, and B12 and minerals such as Calcium, Magnesium, and Potassium, were significantly below the recommendations (p < 0.05) except for vitamin B3 niacin. Conclusions Providing a nutritionally valuable meal is essentially required to maintain both physical and mental fitness. Our results revealed that the Sri Lankan sport science undergraduates do not have an adequate daily dietary intake of energy, proteins, calcium, magnesium, potassium, and vitamins such as C, B1, B2, B9, and B12.