Amyotrophic lateral sclerosis is a progressive, disabling, neurodegenerative disease with upper and lower neuron involvement and, so far, no cure. As the disease progresses, the person with ALS becomes totally dependent, and the caregiver plays a key role in meeting his/her physical, psychological and emotional needs. This paper analyzes the factors associated with the burden and the perception of quality of life of informal caregivers of people with ALS. A descriptive-correlational study was designed, with a sample of available, conducted between January 1 and March 31, 2019, and the following instruments were used for data collection: World Health Organization Quality of Life - Breef to assess the caregiver's perception of quality of life, Informal Caregiver Burden Assessment Questionnaire to determine the level of burden, Amyotrophic Lateral Sclerosis Functional Rating Scale Revised to assess the functionality of the person with ALS, and Amyotrophic Lateral Sclerosis Assessment Questionnaire to assess their quality of life.