To improve the rock-breaking performance of the hob in the process of hard rock roadway excavation, an experimental study on the influence of the cutting speed of the TBM hob on the rock-breaking performance under the action of prefabricated slits was carried out. In order to eliminate the uncertainty of the results caused by the non-uniformity of the slit depth distribution, on the basis of replacing the abrasive jet cutting process with the prefabricated regular slit, combined with the hob cutting load, specific energy and temperature indicators, the influence of the slit depth and its relative lateral distance to the hob on the rock breaking performance was studied from multiple dimensions. Additionally, the influence of the cutting speed on the cutting load and temperature of the TBM hob was analyzed, and the interaction relationship between the cutting speed, the depth of the cutting gap, and its relative lateral distance to the TBM hob was explored. Finnaly, the adjustment direction of the slotting parameters during the matching installation of the hob with a larger radius is obtained. The results show that when the cutting speed increases from 1.0 m/min to 3.0 m/min, the hob load increases by 15.04%, 43.83%, 89.79% and 161.84% respectively, and the maximum temperature of the hob increases by 30.01%, 87.51%, 121.26% and 134.55% respectively. The recommended cutting speed optimization range is 1.0~1.5 m/min. If the rock breaking efficiency of the hob needs to be considered at the same time, the cutting speed can also be relaxed to 2.0 m/min, but the cutting specific energy of the hob will be increased by 19.51%.