Abstract: The nuclear data acquisition and processing can convert nuclear particle energy into corresponding pulse amplitude by analog amplifier, and then the digital information of pulse amplitude is acquired by the analog-to-digital converter (ADC) or time digital converter (TDC). In this paper, the eigenvalue was extracted by the method of pattern recognition from the discrete data, and the analog circuit fault diagnosis and location was studied based on support vector machine. By the experiment of practical forming amplification analog circuit, the validity of the nuclear detector circuit fault diagnosis based on support vector machine was verified.