The study examines the economic costs of insecurity and terrorism on the Regional growth and development in the North-Eastern States in Nigeria. The study investigated how insecurity and terrorism challenges have stifled economic growth and development in the North-Eastern region by disrupting agricultural activities, trade, and investment inflows, which are the primary economic drivers in the region. The Augmented Dickey-Fuller (ADF) was used to determine the stationary status of all variables to ascertain the level of their interaction. The data were analyzed using the Autoregressive distributed lag (ARDL) model and bound test approach to explores the resulting decline in GDP, Unemployment and Inflation rates, and government expenditure. The results of the ARDL estimates reveals that in the long-run, insecurity index has negative impact on the Gross Domestic Product (Economic growth) and statistically significant at 0.5% level. Unemployment rate has a negative economic impact on the Gross Domestic Product in the short-run and statistically significant at 0.5% level. Government expenditure also has negative impact on the real GDP and significantly positive. The finding reveals that insecurity and terrorism has not only constraint the economic growth and development of the region but also led to untold hardship, poverty and increased dependence on humanitarian. The study concluded with the following recommendations amongst others; Government should address the root causes of insecurity by investing in education, healthcare, and economic opportunities in vulnerable communities.