A series of technical measurements for dust-laying in demolition blasting of building of a sport center in Guangzhou are introduced in this paper. The comprehensive measurements involve clearage of surface dust, storing up water on floors, moistening walls, water bags on roof, high pressure sprinking water film, smoke controlled by dust barreir and helicopter ventilation. Forecasting dust with diffusion model of normal distribution and non-border was proposed. Harm of dust pollution to urban district has been reduced ever since the application of the model.