This paper examines tax-induced income shifting behavior among affiliated firms in Korean business groups (chaebols). Korean corporate income tax law does not require consolidated tax returns, and business groups with a large number of affiliated member firms have incentives to shift income across member firms to reduce the overall taxes of the group. For a large number of Korean companies that are subject to external audits, we perform univariate and multivariate regression analyses on the income shifting behavior of chaebol firms compared with non-chaebol control firms. Our evidence suggests that tax-motivated income shifting activities exist among chaebol firms, and that the extent of income shifting is found to depend on its effect on non-tax cost factors such as the earnings, leverage, and cash flow rights of the controlling shareholders. We also find that income shifting is more pronounced in chaebol firms where the control-cash flow divergence is relatively large, suggesting that income shifting is affected by the controlling shareholders' opportunism. Our study provides some insights on the intra-group income shifting activities where research is limited.