Among several methods of evaluating the level of development,the level of development in agriculture,education, population, infrastructure and social services and overall socio-economic development of different districts have been estimated by constructing the Composite Index based on seventeen developmental indicators.For this study the 64 districts have been taken as the unit of analysis.The study has found that Bandarban is the first and Dhaka is the last position in agricultural sector.In Education sector Jhalakati is the first and Bandarban is the last in Ranking the districts.Again Bandarban obtained the first whereas Dhaka is the last position in Population sector.In infrastructure and social services sector Dhaka occupied the first and Meherpur is the last position.Chittagong is the best developed district in combined of all sectors whereas Cox's Bazar is as the last.Wide disparities have been observed in the level of development of different districts in these five sectors.At last general suggestions for improving the level of socio-economic development of least developed districts for the combined sectors have been given.