Abstract: The present paper deals with the zuarphologv of the placoid scales of sharks with particular reference to their patterns. 189 species belong to 62 genera, 21 (amities and 9 orders have been iwestited, of which 80 species~based on Chinese specimens and ID9 species are cfuoted from foreign materials. According to their special characte-. ristics of this paper consists of three parts: 1, the patterns of placoid scales of sharks;the morphological characteristics of placoid scales of sharks in different tags of classification;3. discussion and conclusion,