The Fabry-Perot demodulation method suffers from low sampling frequency, leading to errors when measuring physical quantities with high frequency variations. To address this issue, this paper proposes a high-performance multi-channel fiber Bragg grating wavelength demodulation system using a tunable laser, designed to meet the application requirements of fiber Bragg grating sensors in high-precision and high-frequency measurements. A fast synchronous refresh program was developed to enhance the demodulation frequency and real-time performance, while a dual-core data processing program was implemented to optimize data processing efficiency. Functional and performance tests were conducted using a motor and an isometric beam. Results showed that the proposed system achieved a scanning frequency of 100 Hz and an average fitting error of 6.23 pm, significantly outperforming the comparison system with an average fitting error of 24.10 pm. The linearity reached R2=0.999 9, higher than the comparison system′s R2=0.999 5, validating its feasibility in high-performance fiber Bragg grating demodulation applications.