Since tax systems were introduced several centuries ago, the determinants of tax compliance were different among countries. This paper attempts to reveal the determinants of tax compliance in Malaysia in a self assessment system with reference to political affiliation factor. The objective of this study is to identify the relationship between taxpayers political affiliation and tax compliance when a new tax system is introduced called Self Assessment System (SAS). Nine tax compliance determinants were examined namely probability of being audited, perception of government spending, perception of equity and fairness, penalty, financial constraint, changes of current government policy, referral group, the role of the tax authority and political affiliation. From a survey of 350 respondents, the results suggested that political affiliation has a significant impact on tax compliance. The results also indicate that tax compliance is also influenced specifically by probability of being audited, perceptions of government spending, penalties, personal financial constraints, and the influence of referent groups. The results of this study can inform policymakers in what ways the determinants can affect compliance. It also provides an indicator for tax administrators of the relative importance of political affiliation in assisting with the design of tax education programmes, simplifying tax systems and developing a wider understanding of taxpayers’ behaviour.