Fine structure of dormant and swollen conidiospore from Trichoderma koningii and the mechanism of protoplasting from the conidiospore were studied by scanning and transmission electron microscopy. The cell wall of dormant conidiospore was two-layered structure which consisted of electron dense outer layer and electron transparent inner layer. After 8.5 hrs incubation. the conidiospore was swollen and the outer layer of cell wall shown unequal thickness and partial breakage. Protoplast was released through the pore which has been formed by the breakage of outer layer and dissolution of newly synthesized cell wall for germ-tube formation. Swollen conidiospore and protoplast in releasing process contained various cell organelles and vacuoles with electron dense materials. The protoplast contained looser cytoplasm and had no cell wall materials outside of plasmamembrane.