Firms are so difficult to finance in the capital markets that they usually rely on internal funds to invest R&D projects, which often consist of high information asymmetry and high risk. Both business group and family firms have competitive advantage in capital markets, and therefore, this study investigates how the business groups and family firms in Taiwan influence R&D activities. The results support the hypothesis that contrary to family firms, business groups can mitigate the dependence on the cash flow when financing R&D investment. Moreover, this phenomenon is more obvious under the financially constrained business groups and family firms.