This study examines the cost efficiency of 39 microfinance institutions across Africa, Asia and the Latin America using non-parametric data envelopment analysis. Our findings show non-governmental microfinance institutions particularly; under production approach, are the most efficient and this result is consistent with their fulfillment of dual objectives: alleviating poverty and simultaneously achieving financial sustainability. However, bank-microfinance institutions also outperform in the measure of efficiency under intermediation approach. This result reflects that banks are the financial intermediaries and have access to local capital market. It may be possible that bank-microfinance institutions may outperform the non-governmental microfinance institutions in the long run.