Individuals with autism spectrum disorder (ASD) encounter various challenges related to diet and nutrition, including atypical responses to food to gastrointestinal (GI) problems such as constipation. These challenges may significantly influence dietary choices and health outcomes, potentially predisposing individuals with ASD to chronic conditions such as obesity and cardiovascular diseases. Children with ASD exhibit problematic mealtime behaviors and are often considered picky eaters by their parents compared to non-autistic peers. Additionally, sensory processing disorders or impairments may interfere with their food intake. Children with ASD experience up to five times more feeding problems compared to typically developing children, including food selectivity characterized by restricted food intake and refusals. Various factors such as motor development, sensory processing impairments, and GI issues contribute to food selectivity. Food allergies or intolerances may exacerbate GI issues, further impacting food intake and gut health. Research suggests a link between ASD and gut microbiota dysbiosis, mucosa permeability, and immune dysregulation. Poor dietary patterns in children with ASD, favoring energy-dense snacks and ultra-processed foods, have been reported. Studies also indicate lower intake of essential nutrients in children with ASD, potentially leading to nutrient deficiencies and associated health complications. While dietary supplementation and special diets are explored in a number of studies, evidence on their effectiveness is inconclusive. Feeding therapy and family-centered interventions have shown a promise in addressing feeding difficulties and improving eating behaviors among children with ASD. The chapter discusses research studies that examined feeding and nutritional challenges experienced by individuals with ASD, predominantly focusing on children and adolescents, along with potential solutions addressing these issues.