The aim of the project is to study the present and recent thermal conditions in the sedimentary basins of the Czech Republic. The thermal history of basin sediments is investigated by a number of methods, which give quantitative information on the temperature of the formation and the time of exposure at this temperature. The methods of determination of coalification degree, of illite crystallization and content and composition of fluid inclusions are used. The determination of present thermal conditions is established by the measurements of temperature in the borehole, the thermophysical parameters of rock and by the mathematic modelling. At the present time the history of the Barrandian Basin and Blanice Furrow are investigated. The degree of sediments alteration was examined by means of reflectance of vitriniteas, solid bitumens and graptolites. The research into fluid inclusions on quartz crystals separated from veinlets reveals the presence of abundant brightly blue and yellow fluorescing primary fluid inclusions composed of light oils.