A sapphire anvil cell, a portable system having a sample volume of about 400 mm(3) (Phi8x8 mm), has been developed for gas hydrates research under high pressure. As both pressure and temperature of the sample can be precisely monitored in real time, the system has significant advantages for gas hydrates research at the pressure range of 1-40 MPa and temperature range of 250-350 K. We have applied this sapphire anvil cell system to carry out experiments for investigating the formation and dissociation of CO(2) hydrate. In addition, the developed sapphire anvil cell can be used for in situ thermal, electric, ultrasonic, visible light, Raman, and IR measurements.