Breakfast is often referred to as the "most important meal of the day" in shaping diet quality. This study established the patterns of breakfast consumption in Malaysia and assessed its contribution to the overall quality of the diet based on the 24 h recall data from the nationally representative and cross-sectional Malaysian Food Barometer (MFB, second data collection, 2018) to assess breakfast intake among adults (n = 1604). Diet quality was measured using the Nutrient Rich Food index (NRF) 9.3. The nutritional profile of breakfast was compared across tertiles of NRF 9.3. Overall, 89% of Malaysians consume breakfast. Breakfast was found to provide 474 kcal on average. The Malaysian daily diet was found to be rich in fats, saturated fats, total sugars, and sodium, with breakfast making a significant contribution to the daily intakes of these nutrients. Intakes of fiber, potassium, calcium, vitamins C and D, folate, iron, zinc, and magnesium were low. Breakfast was related to the overall diet quality measured by the NRF index. This study revealed that the breakfasts consumed by Malaysian adults were found to be nutritionally unbalanced. This analysis could serve as a basis for nutrient recommendations grounded in existing social and cultural breakfast patterns.