International Journal of Electrical and Computer Engineering (IJECE) Vol. 9, No. 6, December 2019, pp. 4850~4859 ISSN: 2088-8708, DOI: 10.11591/ijece.v9i6.pp4850-4859  4850 Journal homepage: http://iaescore.com/journals/index.php/IJECE Comparative study of several operation modes of AES algorithm for encryption ECG biomedical signal Mustafa Emad Hameed 1 , Masrullizam Mat Ibrahim 2 , Nurulfajar Abd Manap 3 , Mothana L. Attiah 4 1,2,3,4 Centre for Telecommunication Research and Innovation (CeTRI), Faculty of Electronic and Computer Engineering (FKEKK), Universiti Teknikal Malaysia Melaka (UTeM), Malaysia 1 Department of Computer Techniques Engineering, Bilad Al-rafidan University College, Diyala, Baqubah, Iraq Article Info ABSTRACT Article history: Received Feb 27, 2019 Revised Apr 9, 2019 Accepted Jun 26, 2019 Biomedical signal processing provides a cross-disciplinary international forum through which research on signal and images measurement and analysis in clinical medicine as well as biological sciences is shared. Electrocardiography (ECG) signal is more frequently used for diagnosis of cardiovascular diseases. However, the ECG signals contain sensitive private health information as well as details that serve to individually distinguish patients. For this reason, the information must be encrypted prior to transmission across public media so as to prevent unauthorized access by adversaries. In this paper, the proposed the use of the Advanced Encryption Standard algorithm (AES), which is one of a symmetric key block cipher with lightweight properties for enhances confidentiality, integrity and authentication in ECG signal transmission. However, some of the challenges arising from the use of this algorithm are computational overhead and level of security, which occur when handling more complex.The AES algorithm has different operation modes using three different key sizes which can be utilized in encrypting the whole sample of ECG biomedical signal in electronic healthcare. The experiments in this research, exhibit comparative study of using five modes of operation in AES algorithm, which are coupled with three key sizes based on the execution time and security level for the encryption of ECG biomedical signals in electronic healthcare application. Thus, we reported that the CBC mode of the AES algorithm is suitable to be applied of security purpose. Keywords: AES algorithm Decryption ECG signal Encryption Security Copyright © 2019 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: Mustafa Emad Hameed, Department of Telecommunication Engineering, Faculty of Electronic and Computer Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka, Malaysia. Email: mihhh221@gmail.com 1. INTRODUCTION The biomedical Signal places emphasis on contributions to research in association with practical and applications with regard to the application of ways and devices in clinical diagnosis, tracking of patients and management [1]. Electrocardiogram (ECG) is broadly used in medicine to monitor minute electrical changes on the skin of a patient’s body which arise as a result of human heart activities measured using electrodes placed on standard 12-leads (also referred to as channels) [2]. This is a simple technique and noninvasive measurement which easily indicates a number of heart diseases and the medical industries have built a dedicated equipment that aids in diagnosis of the signal [3]. Contrary, to other biotech authentication methods, the patient can wear the system, and as long as it is worn, authentication can be sustained. Therefore, the violation of the information confidentiality, integrity and accessibility may cause the damage