The study examined the effect of tax audit on compliance in South Western Nigeria. Four hundred (400) questionnaires were delivered to taxable individuals in the states of Osun, Ogun, Ondo, and Ekiti, Oyo, and Lagos States, which together comprise the South-west zone. The data for the study were acquired through the administration of a questionnaire utilizing the cluster sampling approach. In each of the states, a total of one hundred (100 respondents) questionnaires were handed out. When putting the stated hypothesis to test, the ordinary least square (OLS) method was used. According to the findings of the research conducted in Nigeria, there is a correlation that is both positive and statistically significant between the independent variable (tax audit) and dependent variable (tax compliance). According to the findings of the research, a positive and statistically significant relationship exists between tax audit and tax compliance in Nigeria. This suggests that the independent variable contributes to an increase in tax compliance. According to the findings of the research, it is advised that persuasive tax measures, such as tax education and tax justice, be combined with deterrent tax measures, such as tax audits, in order to enforce tax compliance.