The influence of slits on sheet shaped cavitation at the leading edge of hydrofoils was studied using the Mixture multiphase flow model and Schnerr Sauer cavitation model. Analyzed the pressure and velocity cloud maps at different slot angles, and discussed the suppression mechanism of slot on sheet-like cavitation. The research results indicate that the return jet is the main cause of instability in bubble formation; A jet is generated at the slit outlet, which interferes with the return jet that causes bubble detachment, thereby suppressing the growth and detachment of bubbles. Meanwhile, when the angle between the slits is greater than 55 °, the smaller the actual bubble size in the latter half of the airfoil, the more significant the cavitation suppression effect.