BackgroundAmyotrophic lateral sclerosis (ALS) is the most common, fatal adult neuromuscular disease. It is a multi-system disorder characterized primarily by motor manifestations, but there is established evidence for cognitive and behavioral impairment, which is associated with poor prognosis, hence, the importance of tools for its assessment. The Edinburgh Cognitive and Behavioral Assessment Screen (ECAS) is an invaluable assessment tool for cognition in ALS-front temporal spectrum dementia (FTSD), as it accommodates physical challenges that usually confound traditional neuropsychological testing in those patients.Objective and methodsTo validate the Egyptian Arabic version of ECAS (ECAS-EG) based on the original English scale. This is a prospective study. The ECAS was adapted and administered to 62 Egyptian ALS patients and 60 healthy controls. Patients were recruited from the Neuromuscular Unit, Ain Shams University Hospital. The ECAS was adapted to Egyptian Arabic after being translated using the back translation method. Internal consistency of the test, inter-rater reliability, and construct validity were assessed.ResultsThe Egyptian Arabic version of ECAS (ECAS-EG) showed good internal consistency using Cronbach’s alpha of 0.84. Inter-rater reliability was tested, values for all variables were compared, and no statistically significant differences were found (ICC = .997). ECAS-EG discriminated significantly between the patients from the control subjects (p-valueof 0.001). There was a strong positive correlation between the ECAS-EG total score and the MoCA total score with ap-valueof 0.001, thus indicating convergent validity. The test showed that 63% of Egyptian ALS patients were cognitively affected; most affected domains were executive functions and verbal fluency.ConclusionThe current study proves that the Egyptian version of the ECAS (ECAS-EG) is valid and reliable among Egyptian ALS patients and it would be applicable to the general Arabic-speaking population.Supplementary informationThe online version contains supplementary material available at 10.1007/s10072-023-06639-6.