China is the largest country in terms of the purchasing power parity (PPP); and the country has started to invest hugely in the developing countries of the Southeast Asia, South Asia, Africa, Central Asia and the Middle-East. It wants to be connected with Europe, Africa and Middle East through its economic corridors such as BCIM, BRI, MSR and OBOR. It can be mentioned here that most of the South and Southeast countries are poor and need huge investment in the infrastructural projects. Therefore, the concept of BCIM is a win-win geostrategic and economic policy for South, Southeast and China. On the other hand, India is largest country in terms of the size of population; and its economy is also rising rapidly. And this country also needs huge investment and development cooperation from the different countries including China. Besides, Bangladesh is a lower middle-income country; it also wants to grow rapidly in terms of economic growth, transfer of technology and infrastructural developments. On other hand, Myanmar is a developing country in Southeast Asia which requires vast developments, transfer of technology, foreign investments in the coastal regions and regional connectivity for economic growth and development. Therefore, carrying out study on BCIM economic corridor is extremely important in the region. It’s a qualitative study in the context of mythology. This study has found that implementation of BCIM economic corridor is very important for South and Southeast Asia including Bangladesh for regional connectivity, trade and investment and development cooperation.