【Objective】Accurately assessing soil cumulative infiltration is essential to many field irrigation management and saline soil amelioration projects. However, the measurement of soil cumulative infiltration using the conventional methods has a number of defects, like costly, destructive and time-consuming. In addition, because soil infiltration is spatially variable, these point measurement techniques are of limited value in assessing the soil cumulative infiltration over a large area. The technique of Ground Penetrating Radar (GPR) can be used to collect the data non-destructively and instantly over a large area. Therefore, the technique is much higher than the conventional methods in potentiality and applicability for use to assess soil cumulative infiltration on a field scale.【Method】In order to show that soil cumulative infiltration can be extracted from low frequency GPR data in the case of a loamy soil, a controlled soil and irrigation experiment was carried out. During the experiment, a 250 MHz antenna was used to collect GPR data for analysis of radargrams before and after the irrigation. Based on the radargrams obtained a soil infiltration estimation model was constructed using the electromagnetic wave amplitude recorded by the GPR. Then the model was compared with the electromagnetic wave speed model in accuracy and time window stability.【Result】Results show that the determination coefficient of electromagnetic wave speed and soil cumulative infiltration was 0.8, 0.1 and 0.12 in the 2.2m time window, 1.57m time window and total of the samples, respectively, indicating that the electromagnetic wave speed model depends on time windows, and is low in stability and precision, so the model is not good enough to reflect soil cumulative infiltrations. While GPR amplitude was found to be more sensitive to variation of soil cumulative infiltration. Among the electromagnetic wave amplitude parameters, the determination coefficient of trough amplitude of Reflection Wave I and soil cumulative infiltration was 0.999, 0.986 and 0.962 in the 2.2 m time window, 1.57 m time window and total of the samples, respectively, and the determination coefficient of the trough amplitude of Reflection Wave II and soil cumulative infiltration was 0.981, 0.999 and 0.925, respectively.while the determination coefficient of trough amplitude of the ground direct wave and soil cumulative infiltration was 0.920, 0.965 and 0.943, respectively. By following the principle of the highest determination coefficient, this paper selected the trough amplitude of Reflection Wave I in constructing the GPR model for detection of soil cumulative infiltration, thus bringing the determination coefficient up to 0.96.【Conclusion】In brief, the electromagnetic wave amplitude model is higher than the wave speed model in precision and stability, and can be used to monitor and estimate soil cumulative infiltration. The trough amplitude of Reflection Wave I is an ideal indicator to be used to effectively monitor soil cumulative infiltration. Therefore, the low frequency GPR can be used to accurately detect soil cumulative infiltration. All the findings in this research may provide a new way for the detection of soil cumulative infiltration on field scales, and also a scientific basis for further application GPR to the filed of soil science.