Real-time monitoring of medical records and informing the units in emergency situations are very important. Especially in aging societies, taking precautions will reduce a lot of health problems. A portable monitoring unit that contain three-electrode electrocardiogram (ECG) and body temperature sensor is designed. The acquired data is digitally signed with longitudinal redundancy check and RSA algorithms and send to the personal digital assistant (PDA) pocket pc using Bluetooth wireless communication technology. PDA displays and stores the medical records and forwards them to the central server in emergency situations using wireless local area network or GSM/GPRS. Therefore, the developed system enables to monitor patients outside of hospitals without restricting the daily activities of them. The data transferred between portable monitoring unit and PDA is digitally signed. Thus, data security and integrity are achieved.