Results: median age of ALS onset was 54.93 ± 14.08 years (men = 56.21 ± 12.58, women = 52.36 ± 16.49). The sex-ratio was 2.0 with obvious male predominance. Juvenile ALS form was found in 5.71% of our cohort and 94, 76% of the patients had the classic ALS form. In the latter, 76.3% had spinal onset whereas bulbar onset was seen in 20.1% of patients. Spinal onset was most frequent in Juvenile ALS patients. Approx. half of the ALS patients used Riluzole (58.5%). Median survival rate was 60 mo (5 years). According to univariate anal., the factors related to survival rate of ALS patient were: age at onset, diagnostic delay, site of onset, phenotype and treatment use. The multivariate anal. revealed that age at onset, gender, diagnostic delay, superior muscles atrophy, treatment use, consanguinity, cognitive signs, dysautonomia, and ALSFRS-R score were independent prognostic factors of survival among ALS patients. Conclusion: Our Tunisian cohort was characterized by a slower disease progression and a better prognosis. Juvenile ALS patients were more common. Initial ALSFRS-R scores were higher in our population. Age at onset of Bulbar ALS was younger. Our study highlights the possible presence of genetic and environmental factors that may influence the clin. phenotype of ALS in Tunisia.