Objectives: Analyze differences in neuropsychological performance of executive functions in patients treated with peritoneal dialysis (PD) and hemodialysis (HD), and to assess the level of impact of treatment modalities (HD vs PD) and the demographic and clinical variables over cognitive function. Materials and methods: Cross-sectional study with non-probability sampling that included 40 patients with chronic renal failure (CRF) divided into two groups, 20 patients undergoing peritoneal dialysis and 20 in hemodialysis. It was used a battery of neuropsychological tests including test Stroop words and colors, Part B of the Trail Making Test (TMT), Tower of Hanoi, and indirect Digit subtest of the Wechsler scale; and a questionnaire on demographic and clinical variables. Results: Significant differences were found in the number of errors of TMT B and the number of movements of the Tower of Hanoi, with the PD patients who performed better than patients undergoing HD. Moreover, years of schooling and the age of patients appear to have a significant effect on performance in the neuropsychological tests used. Conclusions: Patients undergoing peritoneal dialysis have better performance on executive function tests, but this performance is modulated by the years of schooling and age. It is discussed the role of schooling and age on neuropsychological performance and possible causes of the differences in the evaluated groups.