Minerals dusts are harmful to human health when a great amount of dusts, especially fibrous dusts, are taken into a human body. Through the digestive system, these dusts will come into the stomach and then are dissolved by acid and no influence will be exerted on health, but when dusts come into the breathing system, their reaction with the human body is very complex. They can move, be deposited, penetrate or be dissolved, and may cause cancer or silicosis. The dissolving process is simulated in this study.SEM analysis was made of the residues of mineral dusts dissolved in the simulated human body fluid———Gamble solution, organic acid and inorganic strong acid. The results have revealed the following: the fibers of the fibrous mineral dusts become shorter, the length diameter ratio is reduced, the flexibility weakens, the ends become rounded and a part of fibers are dissolved and become strings of beads; the coarse grains are loose and collapsed and their surface roughness increases; planar dusts become granulated and fine; silicate mineral dusts have a tendency to be dissolved into subspherical nanometer_sized grains composed dominantly of SiO2.The authors further propose that it is of great value to study of the nosogenesis by dusts on the nanometer size.