The study is among the first few studies on Islamic banking that will provide comprehensive cross countries between Islamic banks in the world using more than one analytical approach. Hence, the study also provides contribution in term of rigorousness of the methodology used as compared to previous studies on Islamic banks. This study will contribute findings for 3 different methods used from efficiency, determinants of the efficiency, the profitability and the relationship between efficiency determinants and profitability. Hence, it provides a more comprehensive analysis whereas most studies in the past applied specific model such as Data Envelopment Analysis (DEA) or Tobit or Fixed Effect Model (FEM) on an individual basis instead of employing the three methods in one study. The findings from this comparative study will add an interesting dimension to the existing literature and body of knowledge in relevant manners. This study is novel in presenting new finding on the impact to the Islamic banks on several latest issues such as Financial Crisis (AFC), 2008 Global Financial Crisis (GFC), region in MENA and ASIA, and GNI country income based on 2003 World Bank Atlas method.