This research aims at explaining and comparing the Islamic banking development in Pakistan and Bangladesh, formulated as library research. The significance of this research is duet o the fact that both Pakistan and Bangladesh are two countries with the biggest majority of Muslim in the world, having significant market potential, and the places where several Islamic economic theories founders were born. Therefore, the Islamic economy development, especially the banking system in both countries, is necessary to be observed. This research was comparative descriptive analysis with qualitative analysis. This research concludes that: Both countries have their own characteristics regarding the Islamic banking development. Pakistan has been implementing Islamic system in every sector, including its climax economy that took place in 1985. On the other hand, Bangladesh has developed its Islamic system along with the conventional bank operational as a form of economic democracy which has been initiated since 1983. The development comparison is that Pakistan has been implementing top-down coordination, whereas Bangladesh has been down-top; the government has Islamic vital role in Pakistan, that it could maximize the market potential which reflects high enthusiasm in terms of syariah implementation. Bangladesh has successfully captivated its market through its semi-secular components as well its special treatment within the development, which is considered as variations in boosting the economic benefits.