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Aiming at the problems that most studies required the individual measurement of single soil parameters and there were few studies on the response of multiple parameters to the penetration resistance (PR), taking the clay loam as the research object and a study on the influence of soil moisture content and compaction pressure on the PR was conducted. Six moisture contents and three compaction pressures were set, and the resistance change curves during the process of the probe penetrating the soil under various conditions were recorded. A full-factor experiment was carried out with the final peak (FP) of the probe penetration curve, the relative fluctuation bandwidth (RFBW), and the Fourier energy of the probe penetration resistance curve (PRFE) as the indicators. The results showed that for the ascending effect, when the soil moisture content was increased from 0 to 10%, with the increase of the moisture content, FP was continuously increased, and reached the maximum value of 2.492N at a moisture content of 10% (an increase of 230.94% compared with 0); the compaction pressure had a greater impact on FP at low moisture content, and the impact weakened at high moisture content. For the fluctuation characteristics, when the moisture content was between 0 and 15%, both RFBW and PRFE were decreased with the increase of the moisture content. At a moisture content of 15%, the decrease rate of RFBW was 68.05% of that at a moisture content of 0, and PRFE dropped to 85.80% of that at a moisture content of 0; with the increase of the compaction pressure, both RFBW and PRFE were decreased. When the compaction pressure was 75kPa, the RFBW dropped to 74.62% of that when the compaction pressure was 15kPa, and PRFE dropped to 87.37% of that when the compaction pressure was 15kPa. The research results revealed the influence law of soil moisture content and compaction pressure on the probe PR, providing a basis for the development of soil property testing devices.