Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a devastating neurodegenerative disease that results in pervasive muscle wasting, paralysis, and ultimately death. Recent research efforts have been made to characterize skeletal muscle in the disease, with some evidence suggesting that the tissue may contribute to ALS pathogenesis. Therefore this study was undertaken to continue to describe ALS skeletal muscle, specifically a population of skeletal muscle-specific stem cells known as satellite cells that play a role in regeneration following injury. Satellite cells were isolated and cultured from mutant mice (SOD1 G93A) that recapitulate the disease, assessed for the capacity to differentiate and proliferate, and compared to age-matched control cultures. SOD1 G93A cultures exhibited decreased expression of transcription factors associated with differentiation (i.e. MyoD and myogenin) compared to control cultures, as well as a reduced ability to proliferate in vitro. These results indicate that the satellite cell population in a mouse model of ALS displays dysfunctional myogenic capacity in vitro, and thus may contribute to the atrophic pathology seen in the disease.