Abstract: The conductivity of propped fractures affect the effectiveness of fracturing, so frac design should particularly take into consideration the various factors which affect its conductivity. In order to profoundly interpret the mechanism of the effect of reservoir stress fluctuation on fracture conductivity, laboratory experiments were conducted on researches on reservoirs of different lithologies using core plates of different lithologies as object of study and using the cyclic stress loading to simulate the process of well opening and closing. The experiment result shows that the reservoir stress fluctuation caused by well opening and closing has a very little influence on the conductivity of conglomerate and sandstone reservoirs, and has a relatively large influence on the conductivity of coal rock reservoirs. The wells opening and closing should be kept to minimum.