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As an important tool for agricultural energy conservation and emission reduction, electric tractors are also one of the development and transformation directions of agricultural machinery equipment products in the future. A lot of technical research and product trials have been carried out at home and abroad. Starting with the concept of electric tractor technology, the stages of electric tractor technology development and its typical products are sorted out, and the technical characteristics of each stage of development and the main factors affecting the development of electric tractor technology are summarized. The development of battery technology directly affected the power supply mode and watt level as well as the change of the energy system model of electric tractors. The energy density and the cost of use were the main factors that affected the tractor’s pure electrification. Compared with automobiles, tractors had higher load rates during plowing and rotary tillage. At present, the energy density level that can be achieved by battery products had a certain gap in supporting electric tractors in heavy farmland operations effectively and independently. The development of lowpower pure electric dedicated plant protection models or the use of multiple energy systems on largerpower tractors was in line with the current state of battery technology and can provide common technical reserves for the realization of pure electric tractors in the future. Based on the existing research results at home and abroad, the current research status of the scheme and design, control technology, simulation and test technology of electric tractor research is analyzed, and the characteristics of existing research results in various directions are summarized. It is necessary to continue to form and improve the theoretical system of electric tractors in the future, so as to gradually achieve universal and standardized electric tractor whole machine and implements, agronomy, energy system, new energy generation and rural energy storage technology and application technology matching and collaborative control. Combined with technologies such as Internet of Things, intelligent control and automatic driving to improve the intelligence level of electric tractors, the research results can provide reference for the development of related technologies.