With the advent of ubiquitous healthcare technology to provide a patient with the necessary medical services in anywhere and anytime scheme, the importance of securing safe communication without tampering the medical data by the unauthorized users is getting more emphasized. With this aim, a novel method for constructing encryption keys on the basis of biometrical measurement of electrocardiogram (ECG) is suggested in this study. The experiments on MIT/BIH database show that our proposed method can achieve safe communication by successfully ciphering and deciphering ECG data including premature ventricular contraction arrhythmia signal with compromising its fiducial features as biometric key to transmit the data via the internet network.