To address the limited interference resistance and large size of conventional monolithic triaxial gyroscopes， a novel quad-mass high-frequency triaxial MEMS gyroscope was presented. Compared with traditional gyroscopes， this device had a relatively higher resonance frequency （~30 kHz）， and the size of the sensitive structure was only 3 mm × 2.56 mm. This paper described the sensitive structural form and working principle of the designed gyroscope. Moreover， the width of the beams of the sensitive structure was optimized through a multi-objective genetic algorithm to make the resonance frequency of the working mode higher than 30 kHz and the frequency difference between the drive mode and the sense mode less than 200 Hz. It was fabricated using a three-wafer bonding technology and characterized by a swept-frequency testing system.The experimental results show that the resonance frequencies and quality factors of its drive mode， X-axis， Y-axis， and Z-axis sense mode are 29 692 Hz and 1 274， 31 290 Hz and 354， 29 881 Hz and 305， 30 721 Hz and 393， respectively. The results verify the correctness of the design and research methods， and provide a feasible solution for the development of high-frequency triaxial MEMS gyroscopes.