This study evaluated the safety of laryngeal closure and post-surgical changes in swallowing function of patients with amyotrophic lateral sclerosis (ALS) and proposed an appropriate surgical strategy for patients with ALS. Clinical and surgical data of 26 consecutive patients with ALS who underwent laryngeal closure at Nagoya University Hospital in Japan between 2003 and 2020 were retrospectively analyzed. Changes in swallowing functions were evaluated before and approximately 1 month post-surgery using Neuromuscular Disease Swallowing Status Scale (NdSSS), and Functional Oral Intake Scale (FOIS). The median operation time was 126 min (range, 51–163 min), and the median intraoperative blood loss was 20 mL (range, 0–88 mL). Among the 26 ALS patients who underwent laryngeal closure, grade 1 (mild) complications occurred in three patients (12%); however, no severe complications were observed. After surgery, 25 patients (96%) maintained the swallowing function and only one patient (4%) had deteriorating NdSSS and FOIS scores. No patients were referred to our hospital due to severe aspiration pneumonia after the surgery. Two patients did not require a feeding tube after the surgery and returned to oral intake. Laryngeal closure may be a safe surgical procedure for preventing chronic aspiration and may also maintain swallowing function of patients with ALS. Further multicenter prospective studies using the gold standard videofluoroscopic swallowing examination are required to support our findings.