Abstract: To overcome the depth limitations and interference susceptibility of conventional single-frequency eddy current testing, parameter optimization for multi-frequency eddy current testing probes targeting pipeline defects is investigated. A finite element simulation model is established to systematically evaluate the effects of excitation frequency and coil geometry on inspection sensitivity, followed by experimental validation. The results indicate that the inspection signal amplitude increases significantly with smaller coil inner diameters and more winding turns. Optimal probe parameters are identified as an inner diameter of 5 mm, a height of 6 mm, and 300 turns. Within the frequency range of 10 ~ 50 kHz, cracks with buried depths of 0.5 ~ 2.5 mm can be effectively detected. This study provides a theoretical basis and data support for the optimized design of multi-frequency eddy current probes.