International Journal of Academic Information Systems Research (IJAISR)   Year: 2019 | Volume: 3 | Issue: 9 | Page No.: 7-22 Computerized Management Information Systems and Their Impact on the Job Performance of Employees at Palestinian Cellular Communications Company (Jawwal) Husam R. Ahmad, Nader H. Abusharekh, Mazen J. Al Shobaki, Samy S. Abu Naser Abstract: This study aimed to identify the impact of computerized management information systems on the performance of the employees of Palestinian Cellular Communications Company (Jawwal). The SPSS statistical package was adopted. The study reached several results, the most important of which are the presence of statistically significant impact of the requirements of operation and management of computerized management information systems (hardware, software, human, organizational) on the performance of the employees of Palestinian Cellular Communications Company (Jawwal), and the presence of statistically significant differences between the perceptions of the respondents on the "impact Computerized Management Information Systems (MIS) on the performance of the employees of Palestinian Cellular Communications Company (Jawwal), attributed to the demographic variables (scientific level, years of experience, workplace, job level). The study concluded with a set of recommendations, the most important of which are the following: 1. The need to keep abreast of technological developments in the field of management information systems and to ensure the use of modern hardware, and sophisticated software. 2. Attention to the availability of modern networks and work to solve network problems such as problems of interruptions and slow communication that came within the results of the study. 3. Conduct user and IT courses for operational and application software to increase users' awareness of the capabilities of the hardware and software used and not to focus on how to use it only.