Immunosensors and immunotests are commonly used in medicine, where blood, urine or saliva samples enable concentrations of morphine, progesterone, estradiol, dopamine, insulin to be determined.In this work, the use of immunosensors for the following medical problems is considered: for the quantitative detection of alpha-fetoprotein, for determination of p53 protein in urine for diagnostics bladder cancer, for amperometric determination of carcinoembryonic antigen, for the determination of galectin-3, as biomarker of heart failure, for detecting hepatitis B surface antigen, for sensitive detection of tumor marker for determination of serum level in breast cancer patients.