During more than twenty five years of intensive exploration and research on dinosaurs, the Department of Mineral Resources has discovers over 2,000 bones belonging to several groups of dinosaurs. On the basis of this material, five new dinosaur specimens have so far been described. They are Phuwianggosaurus sirindhornae, Siamosaurus suteethorni, Siamotyrannus isanensis, Isanosauruus attavipachi, and Psittacosaurus sattayaraki. These dinosaurs are important discoveries are increasingly being recognized by both Thai people and foreigners. Many tourists have already visited the Sirindhorn Museum and their number increases every year.