<p>The world’s energy is accelerating towards the stage of deep game, and there is a trend of adjustment, differentiation and reconstruction. Oil and gas resources are still the main source of core competitiveness in the oil and gas industry. As the same time, the production of carbonate reservoirs is limited by geological and engineering conditions, especially in areas with developed fractures. A thermal-hydraulic-mechanical-chemicalmulti-field coupled model is developed in this paper for exploring the acid fracturing productivity of fractured carbonate reservoir. The rock deformation, two-phase flow, heat transport and acid flow reaction are all solved in extended finite element method. The main controlling factors of productivity are studied by combining engineering geological condition in the fractured reservoir, and it involves fracture density, stress sensitivity, fracture morphology and acid fracturing mode. The mechanism of the main controlling factors of productivity are clarified in fractured reservoir. The acidizing modes under different fracture densities are demonstrated and the fracture strategy is determined.</p>