This study investigated the effect of fiscal deficit on selected macroeconomic variables in Nigeria. Specifically the study examined the effects of fiscal deficit on Nigeria's gross domestic product, determine the impact of fiscal deficit on the level of Money Supply in Nigeria, and ascertain the relationship between fiscal deficit and Inflation Rate in Nigeria. To achieve these objectives, the study employed various econometric techniques such as unit root test, Johansen co-integration, ordinary least square and granger causality test in which variations in the independent variables were regressed on the dependent variable using time series data from 1986-2018. Secondary data casing the time frame were collected from Central Bank of Nigeria statistical bulletin. The results of the analysis indicates that (i) Fiscal Deficit (FD) has positive and no significant effect on Gross Domestic Product (GDP) (ii)Fiscal Deficit (FD) has negative and no significant impact on Money Supply (MS) (iii) Fiscal Deficit (FD) has negative and no significant relationship with Inflation Rate (INFR).The study recommended among others that government should set its priority rights, be more committed to budget implementation and to pay more attention to capital expenditure geared towards growth. Systemic corruption which is the main reason why fiscal deficit has not positively impacted on macroeconomic indicators should be dissuaded in Nigeria. The study further recommended that key government institutions should mount programs that are directed towards restoring the value system, norms and mind-set of Nigerians which corruption has destabilized and made weak to be strong again, otherwise, Nigeria will systematically drift into extinction.