Islamist militancy and terrorism, a major sociopolitical issue of Bangladesh today, has largely remained under-researched. This paper mainly explores the forms and ecologies of Islamist militancy and terrorism based on the content analysis of media reports and interviews with some experts in Bangladesh. Ecologies, in this paper, refer to the multiple interrelated and interdependent environments: social, political, and religious, that foster, germinate and nurture the growth of militancy and terrorism. Despite Bangladesh being globally identified as a moderate Muslim country located in South Asia, Islamist radicalization, extremism and militancy have become a major concern since the incidence of nationwide serial bomb blasts in 2005. Althou...