PURPOSE: To facilitate the application of a weed-growth preventing mat which can prevent propagation of weeds or the like without the necessity of weeding, facilitate repairing of cracks, and prevent penetration of rain water, and which can be applied to a curve, a corner or the like with which a mower cannot cope.

CONSTITUTION: A weed-growth preventing mat 4 composed of an outer skin layer formed of unwoven fabric 1, an intermediate layer formed of a bitumen 2, and a lower layer formed of a protecting film 3, is used at a position after peel-off of the protecting film 3, that is, an area where the weed-growth is prevented, is cleaned at first, the exposed surface of the bitumen layer 2 of the mat 4 is laid under pressure against the area, and is press-rolled, or is heated by a burner or the like so as to be melted before it is laid and press- rolled in the weed-growth preventing area.