Using heavy oils and rock samples from Daqing and Liaohe oilfields, laboratory experiments were carried out to investigate the possibility of geocatalytic aquathermolysis of low sulfur content heavy oils. Results showed that for both oils, aquathermolysis could occur, with the addition of minerals into the reaction systems, the reduced rate of average molecular weight and the changes in SARA compositions were enhanced, the viscosity reduction rate increased respectively from 7.41% and 12.95% in simple reactions to 16.05% and 25.29% in mineral-catalyzed aquathermolysis, demonstrating the catalytic activity of minerals in the aquthermolysis of low sulfur content heavy oils.