The objective of this study is to investigate whether the corruption serves as 'grease' or 'sand' in the wheels of Foreign Direct Investment inflow in South Asian Countries, namely Sri Lanka, India, Pakistan, Nepal, and Bangladesh during the period from 2002 to 2018. Using annual time series panel data, the Random Effect method is employed for the analysis. The results derived from the analysis suggest that FDI inflows improve when the perception of the investors over the level of corruption in these countries is favorable to the investment. Therefore, improvement in the perception of corruption towards clean facilitates the foreign direct investment inflow in these countries. Contribution/ Originality: This study is one of very few studies which have investigated the function of corruption in terms of Foreign Direct Investment inflows in case of the South Asian economies. Findings of this study would be helpful to the policy makers to develop investment climate and business people to formulate investment choices. delineates the corruption as an 'abuse of entrusted power for private gain' or 'the abuse of public office for private (economic) gain' which can be the shape of bribery, embezzlement, fraud, favoritism, and extortion and also stated that corruption can be a major obstacle to good policymakers. Excessive patronage, nepotism, job reservations, favor-tofavor, secret party funding, and suspiciously close ties between politics and business are also considered another shape of corruption (Kholdy & Sohrabian, 2008). In addition to that corruption distorts the rule of law and weakens a nation's institutional foundation (Kouneva-Loewenthal & Vojvodic, 2012). Further, corruption may affect the performance of other crucial indicators, such as quality of the environment, personal health and safety, equity and equality, and trust. These circumstances will impact a country's economic welfare and weaken its development Asian Development Policy Review