Abstract <p>The hard X-ray diagnostic is an important system for tokamak, primarily used to measure the hard X-rays emitted by fast electron bremsstrahlung to obtain the intensity and energy information of fast electrons. The system is crucial for understanding physical phenomena such as lower hybrid wave energy deposition location, fast electron intensity and energy, fast electron transport, high energy instability, etc. To meet the demanding requirements of the next generation compact burning plasma tokamak characterized by physics research of high parameters plasma and intense magnetic field environments, it is imperative to enhance both the energy resolution of primary electronic systems and their capability to withstand strong magnetic fields. In this paper, a main electronic system is developed for the diagnostic system of hard X-ray intensity and energy spectrum distribution of the next generation compact burning plasma tokamak. The main electronic system is composed of an analog signal conditioning circuit, ADC (Analog-to-Digital Converter), an FPGA (Field-Programmable Gate Array), and a 10 Gigabit data communication interface, which can analyze multi-channel energy spectrum. Through the testing with ¹³⁷Cs radioactive source, the main electronics system can achieve the energy resolution of 2.9%@662 keV by a CZT (Cadmium Zinc Telluride) detector. It&#xa0;can also operate normally in a strong static magnetic field environment with the magnetic field strength of 160 mT. When operating in the EAST Tokamak, the main electronics of hard X-ray diagnostic can be running stably and providing reliable analytical data.</p>