Since Zöllner described special surgical management of tympanosclerosis, many otologist concentrated with tympanoplastic surgery with the use of operating microscope, there is frequent surgery for tympanosclerosis. In the operating microscopic examination and during operating procedure, there is ample opportunity to observe. Pathological processes were taking place in the tympanic cavity. In the findings made tympanosclerosis, the histogenesis and diagnosis of tympanosclerosis as well as specific operative procedures were discussed in detail. Although extensive light microscopic study and clinical examination of the disease have been carried out, there are still unsolved problems relating the pathogenesis of this disease. Hence the main purpose of this paper is an attemt to explain the origin and nature of tympanosclerosis with semiconductor detacter. In the experimental group treated with inoculation of hemolytic streptococci following incision on the bulla of the guinea pigs with the eustachian tube occlusion. Definitive proliferation of the collagen fiber and thickening of the submucosal layer were observed. In the experimental animals, sacrificed at the sixteenth week, it was shown that some of that vacuole contain amorphous electron dense calcium and phosphorus. In the quantitative semimicroanalysis of ions of the experimental group, electron dense vacuoles phagocytic lysosome or in the electron dense mitochondria in the cytoplasm showed apatite crystals.