Abstract: The conventional acid fracturing technology has become the main measure for the Ordovician carbonate reservoir transformation of Tahe oilfield,but it still exists the problem that it has a short acid etching cracks,limited conductivity and difficult to connect with distant reservoir. In order to solve the problem, the paper proposes a new acid fracturing technology at a very large-scale using more acid fracturing liquids, which connects acid fracturing with sand fracturing organically to increase the fracture length and conductivity. The technology applied in the well TH10411. According to the evaluation after fracturing, the technology has made a great progress in increasing the fracture length, improving reservoir conductivity and connecting the reservoir far from the wellbore, which provides an important technical support for the late development of Tahe oilfield.