The issue of government expenditure being not effectively and efficiently maximized is an age long issue pertaining to Nigeria. The study therefore examined the relationship between public expenditure and Nigerian economic growth. Secondary data was used for the study and was from 1970 till 2020. Two models were used in the study. The dependent variable for the first model was gross domestic product while the independent variables used were capital expenditure, lag one capital expenditure, lag two capital expenditure, and recurrent expenditure. For the second model, the dependent variable was capital expenditure while the independent variables were gross domestic product and external reserve. The two stage least squares regression was used for the study. Findings showed that gross domestic product and external reserve were significant in impacting capital expenditure. Also, capital expenditure and lag two capital expenditure were both significant in explaining GDP. The study then recommended that for past capital projects especially last two years, government should try as much as possible to maintain such projects and keep it in good working conditions.