Abstract: Dust-control treatment of dusty powder, which mainly passes through a 100 mesh sieve, such as pigment and fertilizer, is achieved by, firstly blending the dusty powder with fibrillatable polytetrafluoroethylene and a pair of materials capable of initiating an exothermic reaction upon contact, and then subjecting the blended material to compression-shear under the exothermic reaction and raising the temperature of the blended material to 50.degree.-300.degree. C. The polytetrafluoroethylene fibrillates during the compression-shear and the formed fibrils enclose the dusty powder to turn it to a dust-controlled one.