Abstract: Quantitative evaluation on regional economic growth driven by investment in hydropower exploitation for migrant resettlement plays a key role in the study of benefit sharing. This paper presents a quantitative model for evaluating such growth using the input-output theory, a modified investment matrix, and calculation of economic improvement, along with a case study of the Xiluodu hydropower project and the growth of related industries in Sichuan and Yunnan. The results show that the total value of improvement will reach 4.2-5.2 times that of the initial investment, and great changes will be seen in the industries of metal product manufacturing, machinery and equipment, mining and transportation, the postal, hotel and catering services, and the other businesses. In conclusion, the investment in the migrant resettlement can cause a remarkable growth in the regional economies of Sichuan and Yunnan. This study would help the establishment of a benefit-sharing system of hydropower exploitation in China.