Amyotrophic lateral sclerosis (ALS) is a progressive neurological disease with high risk of malnutrition. Symptoms of dysphagia, depression, cognitive impairment, difficulty with self-feeding and meal preparation, hypermetabolism, anxiety, respiratory insufficiency, and fatigue with meals increase the risk of malnutrition. Malnutrition negatively affects prognosis and quality of life, making early and frequent nutrition assessment and intervention essential. Implementation of an adequate calorie diet, dietary texture modification, use of adaptive eating utensils, and placement of a feeding tube aid in preventing malnutrition. When nutrition status is compromised by dysphagia and weight loss (5%-10% of usual body weight) or body mass index <20 kg/m(2) without weight loss and when forced vital capacity is >50%, a percutaneous endoscopic gastrostomy placement is indicated. When forced vital capacity is <50%, a radiologically inserted gastrostomy is the preferred means of enteral placement due to lessened aspiration and respiratory risk. Parenteral nutrition (PN) is indicated only when enteral nutrition (EN) is contraindicated or impossible. This article reviews the background of ALS, nutrition implications and risk of malnutrition, treatment strategies to prevent malnutrition, the role of EN and PN, and feeding tube placement methods according to disease stage.