Abstract: The geological conditions of hot shales at the bottom of Silurian in the Rub Al Khali Basin were studied based on well drilling data. The w(TOC) test, pyrolysis analysis and Ro test of core and cutting samples were made, indicating that the hot shales are in the mature-high-mature and even over-mature stages. Through the carbon isotopic analyses of kerogen, bitumen “A” and group composition, organic type was confirmed as type II. By means of PetroMod Basin simulation software, the burial history, thermal history and maturity history of 3 wells were simulated. The maturity history of hot shales in contract blocks was simulated as well. The simulation results can be concluded that the forming age of Silurian hot shales in the Rub Al Khali Basin becomes later from the deep sag to the eastern slope, and the hot shales in the deep sag have entered into mature period since the Early Permian; however, the hot shales on the eastern slope became mature from the end of the Early Permian to the end of the Late Jurassic.