Introduction: Today, the importance of social order and security is obvious to anyone. Aside from being one of the most pressing human needs in itself, security is also an important contributor to cultural, social, ethical, scientific, economic. Development. Therefore, public security is a ground for all successes and advances. In addition to executive responsibility in the society, police and disciplinary forces are in charge of administering security. The aim of this study was to evaluate the effect of police performance on the sense of public security in Southern Khorasan Province.Methods: This study is applied in terms of purpose and survey in terms of data collection method. The population included all residents of Southern Khorasan Province in 2011. A sample of 400 people was randomly selected from different cities across the province. A researcher-made questionnaire of sense of security was used for data collection. Descriptive statistics (mean, standard deviation, frequency) and inferential statistics (dependent t-test and independent t-test) were used to analyze data.Findings: The results showed that the police had a high impact on the sense of public security from the perspective of citizens, and that the police played an active role in the provision of (financial, human, economic, ethical, individual, social) security in Southern Khorasan Province.Conclusion: It is required for disciliplinary agencies and stakeholders to plan for coordinated and systematic endevours towards decisive and legal struggle against crime and criminal attempts in society, including fundamental opposition against corruption bands, addiction, evil-doing, and anti-value standards with an aim to create a secure environment in the province.