Abstract: Based on the study of fractured granite reservoirs on Wulanhua sag, the basic characteristics of rock mineral composition, pore structure and fracture formation of granite are analyzed, the difficulties in the reconstruction of blocks are predicted.Drawing lessons from the reservoir transformation mode of unconventional reservoirs, promoting the connection of oil and gas and crack, increasing the contact area of oil and gas and crack, selecting the reservoir reconstruction technology.The combination injection technology of compound fracturing fluid system and full particle size support agent.This technology has been applied to the reconstruction of fractured granite reservoirs in Lan47 well, and has achieved good results.It is of great reference to the exploration and development of granite reservoirs in Wulanhua sag.