【Objective】This study aimed to evaluate the applicability of cosmic-ray neutron sensing (CRNS) for mesoscale soil moisture monitoring in desert photovoltaic (PV) power stations. 【Method】Three desert PV stations and adjacent control areas in Zhangye, Gansu Province, China, were investigated by integrating Monte Carlo N-Particle Transport (MCNPX) simulations with mobile CRNS field observations. Soil moisture was inverted using the N0 parameter method, and spatial representativeness was quantified through neutron weighting functions. 【Result】(1) PV panels exerted negligible interference on near-surface neutron flux. MCNPX simulations revealed a 1.27% relative difference in total neutron flux and a 0.12% difference in the fast neutron range (0.5～1000 eV) between panel-present and panel-absent scenarios. Moreover, mobile CRNS field measurements showed no statistically significant difference (P>0.05) in neutron intensity under panel-present and panel-absent conditions. (2) CRNS-inverted values exhibited strong agreement with oven-dried measurements (R2 = 0.73, RMSE = 0.01 g·g-1), confirming the accuracy of mobile CRNS for soil moisture retrieval in desert PV environments. (3) The effective vertical detection depth and horizontal footprint radius of CRNS were estimated to range from approximately 21～49 cm and 123～151 m, respectively. The mean detection depth within the PV areas (32 cm) was slightly lower than that in the control areas (39 cm). 【Conclusion】Mobile CRNS provides a technically feasible solution for non-invasive, mesoscale soil moisture monitoring in desert PV power stations, offering an innovative approach for hydrological assessment in arid-region solar energy installations.