Expression pattern of Jagged2 gene in mandibular condylar cartilage was examined by means of in situ hybridization (ISH) technique. At E14, Jagged2 mRNA signals appeared in cytoplasm of proliferating chondrocytes. From E15 to E19, Jagged2 mRNA was detected throughout almost all cytoplasm in all layers. However, the distribution pattern was not uniform. These results suggest that Jagged2 plays an essential role for mandibular condylar cartilage morphogenesis and development.