Objectives To investigate the economic burden of percutaneous endoscopic gastrostomy (PEG) in hospitalized patients with amyotrophic lateral sclerosis (ALS) and analyze its influencing factors. Methods Clinical data of ALS patients who underwent PEG between 2014 and 2024 were collected through the inpatient electronic medical record system of West China Hospital of Sichuan University (including age, gender, comorbidities, disease course, daily living abilities, length of hospital stay, hospitalization costs, etc.), and their impact on the total hospitalization expenses were studied. Results A total of 102 patients were included. The median total hospitalization cost for ALS patients undergoing PEG was 12 701.00 (10 412.75, 16 720.00) yuan. The results of multiple linear regression analysis showed that the length of hospital stay and age of patients could affect the total hospitalization cost. Conclusions The total medical expenses for ALS patients undergoing PEG are approximately 10 000 yuan. Early assessment of the disease status in ALS patients, providing individualized management, and optimizing treatment plans to reduce hospital stay and medication costs can effectively control medical expenses.