To provide an environmentally friendly lightweight mulching sheet having excellent light-reflecting properties and weed-proof functions, improving quality of cultivated products during cultivation of vegetables, flowers, fruit trees, etc., with a low load on operators and suitable for agriculture, etc.

The light-reflecting mulching sheet is provided with a light- reflecting resin layer in at least a part of the surface of a filament nonwoven fabric having 2-25 μm filament diameter and 20-100 g/m2 weight and has ≥50% light reflectance. A method for using the light-reflecting mulching sheet comprises laying the mulching sheet having the light-reflecting properties on the roots of the cultivated plants and allowing weeds grown in the ground surface part covered with the mulching sheet to stand without substantially removing the weeds.