The demand for green power agricultural machinery and equipment in modern agricultural production environment is more and more urgent. Among them, the extended-range electric tractor has attracted much attention in the demand for medium and high horsepower, which not only makes up for the lack of battery life of pure electric tractors, but also reduces pollution emissions compared with traditional tractors. Due to the complex operating conditions of tractors (such as ploughing, rotary tillage, transportation, and harvesting, etc.), among them, rotary tillage is one of the most common agricultural operations. In order to promote the diversified development of electric tractor products, taking an extended-range electric rotary-tilling tractor with a dual-motor independent electric drive structure as the object, a novel backward modeling method of a dual-input variable, including the forward speed and the power take-off (PTO) was proposed to set up the energy management model of the powertrain system. The energy management model designed mainly contained a Genset model, motor model, power battery pack model, transmission system (reducer and differential) model, wheel-soil system model, engine accessories, and auxiliary load system models. According to the characteristics of rotary tillage operation, a design method based on the combination of measured data and empirical formulas was put forward to establish a cycle model of rotary tillage conditions, which provided an environment for simulation tests and bench tests. Based on the dynamic programming, the energy management strategy of the extended-range electric rotarytilling tractor was designed, the rotary tillage operation simulation test and the bench test were carried out respectively. The results showed that the simulation results were in good agreement with the bench test results in the aspect of the forward speed, and the maximin average error was 2.18%, which was within the acceptable range, especially when operating at low speed below 0.6m/s, these two results were basically consistent. There was also a high degree of coincidence between the results of simulation and bench test in terms of the rotary tillage torque. The power values of the Genset in the bench test were larger than Genset results of the simulation, which indicated that the Genset module in the simulation underestimated the actual efficiency of the Genset of the bench. Nevertheless, the variation trend of SOC in the simulation was the same as that of the bench test results. In general, the energy management model of the extendedrange electric tractor can well describe the changes in the power of each motor, the power of the Genset and the SOC of the power battery pack during a given rotary tillage condition, and the fuel consumption of the simulation test and the bench test were 4065.5g and 3994.7g, respectively, the relative error was 1.77%, which verified the rationality and accuracy of the established energy management model of the extended-range electric rotary-tilling tractor.