The study examined the effect of public sector financial transparency on corruption mitigation practices.Public participation in budgetary process, budget oversight, and budget transparency were the independent variables of the study, while corruption perception index is the dependent variable. The study adopted ex-post facto research design, covering the period between 2013 and 2022. Secondary data were extracted from Transparency International website and International Budget Partnership website. Multiple regression technique was used for the test of hypotheses. Findings suggest that public participation in budgeting processes showed a statistically non-significant negative effect on the corruption perception index (p = 0.5685, t = -0.603), indicating limited influence on transparency perceptions, budgetary oversight demonstrated a statistically non-significant positive effect on corruption perceptions (p = 0.0704, t = 2.197). However, the most notable finding was regarding budgetary transparency, which exhibited a statistically significant negative effect on the corruption perception index (p = 0.0031, t = -4.760), suggesting that increased transparency may lead to lower perceptions of corruption. This implies that public sector transparency significantly influences corruption perception index in Nigeria. The study made recommendations for three vital areas of governance improvement in Nigeria. Firstly, enhancing public participation in governance processes, particularly in budgetary decision-making, requires raising awareness among citizens, ensuring accessibility for all segments of society, and empowering citizens with the necessary knowledge and skills for meaningful engagement. Secondly, strengthening budget oversight mechanisms is crucial for ensuring accountability and detecting corruption, necessitating investments in capacity-building, transparency measures, and collaborative efforts between oversight institutions and civil society organizations. Finally, promoting budgetary transparency is essential for enhancing public trust and accountability, with recommendations including prioritizing open data initiatives, mandating public disclosure of budgetary information, and encouraging active citizen participation.