This paper compares pore size distributions in different sedimentary facies shales for similar maturity in typical areas, China. Pore size distributions were analyzed using low-pressure gas adsorption, mercury intrusion capillary pressure, and field-emission scanning electron microscopy techniques. Results showed that pore volume and surface area of shales clearly covary with sedimentary facies, total organic carbon (TOC) contents, clay minerals, maturity, and kerogen type.