The invention relates to the technical field of oil well testing devices and in particular relates to a testing device for deep wells and high-temperature and high-pressure wells. The testing device comprises a gas production wellhead, an injection device, a front oil nozzle manifold, a desander, a rear oil nozzle manifold, an emergency blowout prevention valve, a heat exchanger, a blowout prevention pipe, a high-pressure three-phase separator, a heat supply device, a sleeve blowout prevention pipe, a sleeve fracturing truck unit, a jet hole, a fracturing truck unit, oil and a water tank group; the gas production wellhead is connected with the jet hole, the fracturing truck unit, the sleeve fracturing truck unit, the injection device and the sleeve blowout prevention pipe together respectively; the injection device, the front oil nozzle manifold, the desander, the rear oil nozzle manifold, the emergency blowout prevention valve, the heat exchanger and the high-pressure three-phase separator are sequentially connected together; and the upper end of the emergency blowout prevention valve is fixedly connected with the blowout prevention pipe together. The device provided by the invention has the advantages that the structure is reasonable and compact, the use is convenient, the pressure of the formation can be effectively maintained, the collapse of a borehole can be avoided, the sand production rate can be reduced, the liquid-gas flow rate can be smoothly controlled, the desanding can be performed timely, and oil testing and oil production work can be further performed safely.