ADSSL1 myopathy is an ultra-rare neuromuscular disorder caused by mutations in the gene, ADSSL1, which encodes for adenylosuccinate synthetase (ADSS), an enzyme involved in purine metabolism. Patients with ADSSL1 myopathy exhibit progressive muscle weakness, and there is no standard treatment for the disease. Our mutant Caenorhabditis elegans model lacking ADSS exhibits mobility and mechanosensory deficits compared to controls. This animal model of ADSSL1 myopathy can provide useful insights into disease etiology and potential treatments.