Natural gas hydrates are considered highly likely to become the most promising new alternative energy source in the future, attracting widespread attention from countries around the world.The analysis of performance parameters of natural gas hydrates through pressure testing is extremely important for explaining the growth mechanism of hydrates existing in the formation and predicting changes in the physical and mechanical properties of the formation during hydrate decomposition. It is also the key to constructing a prediction model for the occurrence behavior of gas hydrates in the complex situations mentioned above, which is of great significance for evaluating the occurrence mode and resource quantity of natural gas hydrates in the reservoir. Estimating various parameters of hydrate cores using seismic or logging data often results in significant errors from actual values, and it is difficult to conduct in-situ formation parameter testing under existing technical conditions. So obtaining hydrate formation cores through drilling and testing their physical, chemical, and mechanical properties is the most reliable method. A few developed countries and regions, such as the European Union, the United States, and Germany, have successfully developed post-processing and on-site testing analysis devices for hydrate fidelity core samples and applied them in production sites. Currently, China’s on-site testing analysis and post-processing technology for core samples connected to deep marine natural gas hydrate pressure sampling drilling tools is still immature, and most on-site testing relies on relevant foreign detection devices and methods. This article introduces the working principle, key technologies, and related experimental research of a field parameter testing and analysis system for natural gas hydrate pressure retaining core samples. The system is mainly composed of core capture and cutting units, sampler pressure maintaining units, core sample parameter testing units, core sample storage units, temperature and pressure maintaining units, etc. The structure and working principle of each unit are introduced in detail. In order to verify the working performance of the parameter testing system and the influence of different pressure environments on the parameter testing, the system tested the longitudinal wave velocity, resistivity and shear strength of three different hydrate simulation cores under different pressures. Research has shown that the pressure parameter testing system for natural gas hydrate core samples can work stably and reliably at a high pressure of 30 MPa. The influence of pressure on resistivity testing of hydrate core samples is not significant. Pressure has an impact on the wave velocity testing of hydrate core samples, and the higher the pressure, the greater the longitudinal wave velocity. The pressure has a great influence on test of core shear strength.