Abstract: At present, research on the vibration system of the vibration absorber and the single-piston linear Stirling cryocooler is almost entirely carried out on the positive definite model of a certain fixed installation method for the known cryocooler system. Owing to the lack of analysis of the system's natural frequency using this method, resonance may occur, and the damping effect of the vibration absorber may be reduced when the installation method is changed. Therefore, this study conducts a theoretical analysis of the positive semi-definite model of the cryocooler and the vibration system of the vibration absorber without any installation and performs vibration experiments before and after the cryocooler is fitted with the vibration absorber through the suspension test method. The theoretical natural frequency value of the system under the positive semi-definite model is 78.6 Hz. Through experiments, it can be found that, due to the actual processing and assembly of the vibration absorber, the natural frequency of the system changes with the vibration absorber's stiffness within the range of 78.1 to 80.8 Hz.