In Morocco, the number of people aged 60 and over has increased. This draws attention to conditions whose prevalence increases with age including chronic kidney failure and dementia. This population appears to have a higher risk of cognitive impairment. The aim of our study is to determine the prevalence of cognitive disorders in our dialyzed patients, to define the types of this decline and identify the factors associated with cognitive decline. Observational, cross-sectional study of 116 patients taking hemodialysis from El Ghassani hemodialysis center in Fez. We used the Montreal cognitive assessement test before the hemodialysis session, A Moca ≤ 24/30 indicate the presence of cognitive impairment. The Moca was abnormal in 70% of our patients. The average score was lower for women. The areas most affected were attention and short-term memory. We found a strong correlation between the decrease in the Moca score and the progression in age (p <0.001). Hypertension was correlated with a Moca score with an average score in the hypertensive population of 20 ± 5.4 (p <0.006). The relationship between cardiac disease and Moca was significant with an average score in patients with heart disease of 19 (p <0.01). Taking an erythropoiesisstimulating agents were linked to the Moca test (p <0.05). The number of sessions per week was significantly correlated with Moca (r: 0.25, p <0.005). Albumin and hemoglobinemia were correlated with the Moca score (r: 0.2, p <0.027) and (r: 0.2, p <0.02) respectively.