Income smoothing refers to practice by using accounting techniques to reduce fluctuations in net income over several time periods. This actions undertaken by management to achieve the desired profit position in the income statement of the company for the market's interest in investing. The objective of this research was to obtain empirical evidence about the effet of firm size, financial leverage, return on asset, net profit margin, and dividen payout ratio towards income smoothing. In this study, financial leverage was measured by Debt to Equity Ratio (DER), while income smoothing was measurd by Eckel's Index. The objects in this research were manufacturing compaines, which listed at Indonesia Stock Exchange (IDX) for period 2013-2016. The sample was selected by using purposive sampling method. The secondary data used in this research was analyzed by uisng binary logistic regression method. In total, there were 21 companies which fulfill the criteria set by the researcher. The result of this study were: (1) firm size has significant effect towards income smoothing, (2) financial leverage has no effect towards income smoothing, (3) return on asset has significant effect towards income smoothing, (4) net profit margin has no effect towards income smoothing, (5) dividend payout ratio has no effect towards incom smoothing, and (6) firm size, financial leverage, return on asset, net profit margin, and dividend payout ratio simultaneosly have a significant effet towards income smoothing.  This finding lends support to the contention that firm size and return on asset can effect management's decision in income smoothing pracitice. Taken together, this study provides evidence indicating that companies with less asset and profitability have a tendency to do the income smoothing.