Taste acuity for the four primary tastes has previously been shown to be impaired in patients with chronic renal failure (CRF) and maintenance dialysis treatment, although data on CAPD (continuous ambulatory peritoneal dialysis) patients are insufficient. In a test group of 57 CRF patients and 57 healthy controls, matched for age, sex and body mass index (BMI, kg/m2) taste acuity for the four primary tastes was determined. Fourteen patients were on CAPD treatment and 12 patients on hemodialysis (HD). No patients or controls were diabetic, on antibiotic treatment or had a malignant disease. Taste tests were standardized and performed on dialysis-free days for HD-patients. Taste acuity for bitter and salt was significantly lower for preuremic patients compared to their controls. In CAPD-patients taste detection of bitter was impaired and in HD-patients detection of salty taste was impaired. In conclusion taste acuity is impaired in uremic patients and dialysis patients including CAPD. The mechanism for taste alterations remain to be explained.