The paper concerns the development of the heart rate wearable wireless monitoring system “CardioBeat”. This system has two types of transmission mode, which are total signal transmission and heart rate transmission modes. The developed system uses wireless PAN (Personal Area Network), which operates in low-power mode. It is composed of two main parts: ECG registering circuit with wireless communication module and base station with terminal. The registering circuit has three surface electrodes, ECG amplifier and microcontroller. In total signal transmission mode, it can send data with transmission speed corresponding up to 300 ECG samples per second. In heart rate transmission mode, it can calculate heart rate from ECG data with 300 samples per second and send packets at the specified rate. Base station communication unit forwards the received data to PC, where the data can be stored and displayed. The developed equipment showed the possibility of real-time monitoring of the patients in their daily life and is expected to contribute, in particular, to the saving of medical expenses.