Background:The objective of the study was to determine the impact of unethical behavior of the officials of different departments on citizens' trust with reference to good governance in Pakistan. The livelihood, way of life, and general standards of living of the general masses take all benefits from good governance. It is generally acknowledged that effective governance is an essential component in the process of attaining the trust of citizens. Methodology: The current study was quantitative in nature and linear regression analysis with the help of descriptive and inferential statistics was conducted. A three dimensional five point likert scale covering good governance, unethical behavior and citizens' trust was adapted. A sample of 784 male and female was collected from the four provinces of Pakistan. Results: Results of the study revealed that unethical behavior has a significant impact on citizens' trust. Conclusion: It is concluded that governance is directly linked with the performance of government public servants and they are in need of citizens' trust and Officials with Unprofessional and unethical behavior are serious threat for good governance. Recommendation: It was recommended that a transparent accountability system should be launched in order to eradicate different forms of unethical behavior among the government officials so that the trust of citizens might be restored.