The samples of the Lower Cambrian solid bitumen with the characteristics of high organic content, high hydrogen index, and low asphaltene maturity were collected at Kuangshanliang in Guangyuan in the northwest part of Sichuan Basin. The formation porosity thermo-compression simulation experiment was used to launch the generation and expulsion simulation experiments of“solid bitumen +dolostone +deionized water” (Series A) and of “solid bitumen + dolostone + magnesium sulfate + deionized water”(Series B) under reservoir conditions. The results show that two series have quite different ratios of gas yield. Between them, Series B occurrences thermochemical sulfate reduction (TSR), which makes not only increasing the gaseous hydrocarbon and non-hydrocarbon gas yields but also accelerating the heavy hydrocarbon pyrolysis and reducing the temperature of heavy hydrocarbon pyrolysis.