Abstract: Multi-channel gamma-ray spectrometers are necessary for measuring natural and artificial radionuclides. The core of the multi-channel gamma-ray spectrometers is the multi-channel pulse amplitude analysis, which determines the resolution and analysis accuracy of radionuclides. This study introduces the working principle of a multi-channel pulse amplitude analyzer based on linear discharge and describes the methods for analyzing pulse amplitude and obtaining spectrum peaks. Secondly, this study details the design methods of eight important parts of the multi-channel pulse amplitude analyzer, including the design basis, design idea, and feasible schemes. Finally, this study details the logical sequence diagram of the analyzer, laying a foundation for readers to design a multi-channel pulse amplitude analyzer. Using the working principle, design method, and working logic sequence diagram presented in this paper, as well as modern high technology, readers can develop a new type of modern multi-channel pulse analyzer with uniform channel width, excellent differential nonlinearity, and improved resolution of radionuclides, thus better serving the society using gamma-ray spectrum data with higher energy resolution and high measurement accuracy.