Abstract: Highly sensitive force measurement is a crucial aspect in the research of high precision kilogram realization using a Joule balance. Current force measurement methods involving beam balances and commercial mass comparators introduce additional errors in the Joule balance force measurements. In response to this challenge, we propose a design method for a high-sensitivity force sensing device based on multiple flexure hinges. This method uses multiple flexure hinges to translate force into structural deformation, which is then measured using a laser interferometer, enabling highly sensitive force measurements. We have carried out theoretical and finite element simulation analyses to simulate the sensitivity and modal performance of the device. This method can achieve a force sensing sensitivity of up to 8.13 N/m. Our research carries significant implications for the design of next-generation Joule balances and the advancement of kilogram realization studies.