Amyotrophic lateral sclerosis (ALS) is a progressive disease characterized with degeneration in upper and lower motor neuron of brain and spinal cord. 90-95% of disease occurs as sporadic and 3-10% of it occurs as familial. Clinical symptoms begin at the ages of 50-60. Onset age for familial cases is earlier. The disease occurs due to loss of motor cells (neuron) in central nervous system, spinal cord and brain stem. The first symptom is weakness all the time. Clinical symptoms may begin as asymmetric weakness of arm and leg, myoclonia, myolysis or speaking difficulty. Malnutrition may be seen in ALS patients due to difficulty of swallowing. Good nutrition is very significant as it affects the life quality of ALS patients. Weakness may arise from the effect of chin movement, tongue mobility, lip closing or swallowing reflex. Weakness may start slowly and get worse and worse during the course of disease. The disease gets worse and worse in time and patients die due to infections, respiratory insufficiency 3-5 years after the onset of clinical symptoms. 10% of patients may live for 10 years or longer. The best example of it is Stephen Hawking the famous scientist and being ALS in the beginning of the 1960’s.