<正> Six basic types of fibroblasts（low-differentiated fibroblast

young fibrobla-st

collagenoblast

myofibroblast

fibroclast and fibrocyte）were studied ultras-tructurally.In each of its three phases（prophase

metaphase and telophase）

the collagenoblast showed different functional conditions.The fibroclastscontain two subtypes

the phagocysis and the lysosome subtypes

The fibro-cytes consist two subtypes

the resting and aging subtypes.The observationsdemonstrate that the fibroblasts were derived from undifferentiated cellsaround capillaries and the low-differentiated fibroblasts are the youngestcell type of all fibroblasts.The collagenoblasts and fibroclasts are the maincells responsible for collagen biosynthesis and desrdation respectively.In the present paper a new concept

the“Fibroblast System”

has beenproposed

which includes the six basic types of fibroblasts and the stru-cturel as well as functional relationships among them.