There are various factors in operational decision making that need an attention. one of them is cash management. manager have to minimize the company costs by saving enough cash or cash holdings. theory used in this research is trade-off theory, pecking order theory and agency theory. The purpose of this research is to examine investment opportunity set, cash conversion cycle and corporate governance structure to cash holdings in manufacturing companies listed on Indonesia Stock Exchange within the period of 2014-2016. Subjects of this study are manufacturing companies listed on the Indonesia Stock Exchange 2014-2016. The type of data research is secondary data taken from the Indonesia Stock Exchange. this research used purposive sampling method, and Multiple Linear Regression to analyze the data this study used EVIEWS program to analyze multiple linear regression. Based on the description above, it can be concluded that Investment Opprtunity Set (IOS) has significant positive effect on Cash Holding, Cash Conversion Cyle (CCC) and significant negative effect on cash holding while Corporate Governance structure has no effect on cash holding.