The floating net cage business (FNC) has developed in Lake Toba since the 1990s. This activity has become a profitable business for the community and supports the regional economy. However, recently the central government is aggressively seeking to reduce the production of FNC in order to support Lake Toba as a Super Priority Tourism Destination. This condition has disturbed FNC actors because it threatens the existence of their businesses, which also affects the regional economy. The research question is how big is the role of the FNC business on the economy of the Lake Toba area? For this reason, this study aims to analyze the role of the FNC business in supporting the economy in the Lake Toba area. The research method used is a survey method by collecting primary data in the field. Furthermore, the data were analyzed by multiplier effect analysis. The results showed that 64.5% of the total FNC is owned by the community and other FNC companies. FNC activities have encouraged the development of other businesses that are directly or indirectly related. The FNC business creates job opportunities for around 12,300 people. Thus the total business value generated is no less than IDR 4 trillion. These parameters indicate that FNC is an industry that has a very large role in the economy of the Lake Toba Region.