By-products from fruits and vegetables are slices and peels that have been removed or rejected by the food industry and are considered to have low commercial value. Pumpkin peel is a source of carotenoids, minerals, antioxidants and phenolic compounds. This work studied the nutritional value of pumpkin peel flours produced by convective drying (40 °C) and milling. Pumpkin peel flours contained high contents of insoluble fibres (24.46 g/100 g), potassium (19.1 g/kg) and iron (152.5 mg/kg). Carotenoids were extracted using hexane at 40 °C, and flour particles were classified by 35-, 80- and 100-mesh sieves. The total carotenoids content ranged from 216.9 to 306.8 μg/g. Fick’s second law model computed that 215 min was required to extract 99 % of the total carotenoids. This work evidenced the effects of particle size on carotenoids extraction efficiency and demonstrated that pumpkin by-product flour could be used as a food ingredient or natural dye.