This study aimed to determine the role of KIBSs as a tool for sustainable innovation in a country’s economic system. Specifically, the degree and role of their impact on the Korean economy were analyzed and compared for the entire KIBS sector, T-KIBSs (a new technology-based professional service), P-KIBSs (a traditional professional service), and every subsector. For this purpose, the demand inducement model, supply inducement model, and interlinkage effects method were applied using the 2019 input–output table published in 2022. The analysis showed that the indirect production inducement effect of the entire KIBS industry on other industries was KRW 0.800, the indirect added value inducement effect was KRW 0.330, and the supply disruption effect was KRW 1.144. For T-KIBS, the indirect production inducement effect was KRW 0.687, the indirect added value inducement effect was KRW 0.272, and the supply disruption effect was KRW 0.730. For P-KIBSs, the indirect production inducement effect was KRW 1.472, the indirect added value inducement effect was KRW 0.646, and the supply disruption effect was KRW 2.657. Finally, regarding the economic ripple effect of the KIBS subsector, legal and management support services and advertisements corresponding to P-KIBSs showed higher figures than the T-KIBS subsectors in all sectors, including production inducement, the added value inducement effect, and the supply disruption effect. These results revealed that in the South Korean economic system, KIBSs contribute to production and value addition across all industrial sectors. It is apparent that the absence of supply significantly disrupts other industries. Furthermore, production inducement effects are evenly distributed among all the KIBS subsectors in the secondary and tertiary sectors, while the value-added effects have a greater impact on the tertiary sector. In terms of the supply shortage effects, the secondary sector experiences a more significant impact. This underscores the crucial role of KIBSs in sustaining and enhancing overall economic activity in South Korea.