The autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a cerebellar ataxia autosomal recessively inherited characterized by an ataxic and pyramidal syndrome usually occurring near two years of age. The spastic paraparesis progressively worsens and becomes the prominent sign. Sensorial and motor axonal peripheral neuropathy is frequently reported as well as prominent retinal myelinated fibers on fundus examination. Brain magnetic resonance imaging reveals a predominantly vermian cerebellar atrophy. Mutations in SACS gene on 13q11 are responsible for ARSACS. We report two patients from a non-consanguineous French family, affected with ARSACS, due to the compound heterozygous mutations p.Ala2558Val and p.Pro536Leu. The clinical presentation is in accordance with the previously described ARSACS cases, despite the presence of mental retardation, the predominantly demyelinating peripheral neuropathy, and the evidence of asymptomatic generalized spikes and waves on electroencephalography. We described the clinical heterogeneity in this family including the age at onset of the disease and the first signs as well as the rapidity of the disease progression. We present a review of the literature on this rare disease mostly described in Quebec.