To provide a method for simply and effectively preventing an adverse effect in a peripheral environment since a school ground and a vehicle passing part of construction site have the adverse effect by occurrence of dust.

The means for solving the problem is a water-soluble emulsion containing 0.1-20 wt.% of a polybutene. The dustproof agent is sprayed on or impregnated into a dusting soil surface so that fine soil particles being causative substances of dust are bound mutually or on a sandy soil to prevent dust caused by wind, weight pressure and impact of human and vehicle.