Nowadays, it is important for organizations to focus on improving performance, effectiveness, and stakeholder satisfaction, especially in police organizations. On the other hand, human resources as the most important asset of the organizations play the most important role in achieving the organizational goals and mission. Therefore, consideration of the factors that influence the effectiveness of human resources leading to increased organizational performance, including strengthening employees’ communication skills, is an essential necessity. The purpose of this study was to identify the relationship between staff communication skills and the effectiveness of Alborz police units. The present study is quantitative in terms of data, practical in terms of purpose, and correlational in nature. The statistical population of this study consisted of all Alborz police officers who were selected based on simple random sampling and Cochran formula. The research tool was a questionnaire consisting of 26 questions of communication skills of staff and 14 questions of effectiveness. The validity of both instruments was confirmed by face validity and their reliability by Cronbach’ s alpha was 78% and 77%, respectively. Data were analyzed using statistical tests. The findings showed that there was a significant relationship between the dimensions of staff communication skills and the effectiveness of Alborz police units and its correlation was 0. 788. it has been shown. The results indicate that the police can increase their effectiveness in achieving organizational goals by enhancing staff communication skills in Alborz province.