The invention is related to a potentiometric measurement device (1) such that it can be carried by the patient or user easily and it can measure the urea, phosphate and pH values in an amount of blood at every environment such as home, office, hospital which comprises a measurement module (10), a control module (20) and a communication unit (103) which has at least one urea sensing unit (100) for determination of the urea amount in blood, at least one phosphate sensing unit (101) for determination of the phosphate amount in blood, at least one pH sensing unit (102) for determination of the hydronium ion level in blood and which comprises a control module (20) that determines urea, phosphate and pH values in blood via the data measured by the urea sensing unit (100), phosphate sensing unit (101) and pH sensing unit (102) and provides comparing said data with the reference values of healthy humans and presentation to the user.