The study examines the effects of Personal Income Tax Amendment Act 2011 on revenue generation in Nigeria, with a view to exposing the possible challenges and prospects it poses to the Nigerian tax payers. The primary data for this study were sourced using a structured questionnaire while secondary data were sourced through relevant textbooks, academic journals and the internet. The data collected through the questionnaire was analyzed using chi-square statistical method. The study reveals among other things that the increase in the tax rate affected the tax payers revenue generation, and the retroactive nature of our tax laws constitutes a major problem thus: resulting in double taxation during the assessment and collection of taxes. following the findings, the researchers recommends that competent laws should be passed by the government on personal Income tax collection and generation, stiff penalties should be imposed on the tax defaulters and evaders, tax laws should be made less complex, recruitment of qualified personnel to enable them cover fully the scope of work and finally the tax payers should be educated sufficiently on the importance of tax.