Abstract: The CO2 huff and puff increase production technology is one kind of method of enhanced oil recovery. The mechanism is that CO2 can change the physical quality of oil when it dissolving in oil under the condition of formation, so the viscosity of oil has been depressed and the energy of CO2 drive has been increased. Field testing indication that the technology have evidence increase productivity effect. The condition to select well and the effect of some wells after using the technology was introduced.