The invention discloses an ultra-thin breast pad and a preparation method thereof and relates to the field of female lactation products. The ultra-thin breast pad is composed of a surface layer hydrophilic non-woven fabric, an intermediate absorbing layer and an impermeable bottom film. The surface layer hydrophilic non-woven fabric is a soft type double-component filament non-woven fabric composed of core layer PP / skin layer PE; and the intermediate absorbing layer is a hot melting non-woven fabric formed by blending core layer PP / skin layer PE and superabsorbent fibers. According to the method for preparing the ultra-thin breast pad, the surface layer hydrophilic non-woven fabric for preparing the ultra-thin breast pad is selected through a PE/PP double-component filament non-woven fabric soft bulkiness processing method, the superabsorbent fibers and the PE/PP double-component fibers are blended, the intermediate absorbing layer is prepared through a plain net hot air reinforcing method, so that the prepared ultra-thin breast pad has the advantages of being not subjected to fiber slip, being ultra-thin and breathable, having moisture breathability and being safe and healthy, and the problems that a breast pad not subjected to fiber slip is poor in comfort, unsafe, high in moisture content and high in material cost are solved.