The problem of insecurity and terrorism became heightened in 2014 after a series of attacks by Boko Haram on individuals, properties; government installations, etc. especially in North-East Nigeria. The study examines Boko Haram Insurgency and sustainable development in North East Nigeria, using the thematic approach of Insurgency and sustainable development. Qualitative analysis was strictly used based on purposive sampling gathered from four states of the northeastern part of Nigeria; Borno, Yobe, Bauchi, and Gombe. The Sustainable Development Theory was used to analyze the Insurgency's impact on economic, social, and human development, and the climate/environmental challenges. The researcher used both primary and secondary sources to collect information. The research findings indicate that the North East region and its people suffered grievous economic and political damages from the activities of the insurgents, with the catastrophic collapse of economic, social, and political structures, and processes, and a likelihood of the State itself collapsing and breaking into fragments if the insurgency had continued unabated for a more extended period. The study recommended that the provision of immediate and comprehensive mental health diagnosis, treatment, and counselling will play an essential and critical role in helping people exposed to insurgency recover quickly from the emotional pains and trauma that come with such exposure.