A 52-year field experiment investigated the impact of farmyard manure (FYM) on soil hydro-thermal properties in pearl millet-wheat cropping system. FYM was applied at different rates (0, 5, 10, and 15 t ha-1) during rabi and both kharif and rabi seasons. Long-term FYM application increased soil organic carbon by 56.8% (rabi) and 88.2% (both seasons) compared to control treatment at 0-30 cm depth. Application of FYM decreased the soil bulk density to 0-30 cm depth. Saturated hydraulic conductivity increased by 55% for FYM applied in rabi and 93% in both seasons at 0-30 cm depth. The infiltration rate increased by 46% (rabi) and 96% (both seasons) with long-term application of FYM at 0-15 cm depth. Both saturated hydraulic conductivity and infiltration rate were positively correlated with SOC and negatively correlated with bulk density. Diurnal soil temperature variation decreased with higher FYM levels, while soil moisture increased to 30 cm depth. Soil specific heat capacity ranged from 1.68 to 1.83 J m-3 0C-1 x 106, thermal diffusivity of 3.73 to 4.55 m2 s-1 x 10-7, and thermal conductivity of 13.14 to 15.91 W m-1 degrees C-1. With application of FYM, wheat grain yield was shown to increase in all treatments, and the maximum yield observed 6250 kg ha-1 when 15 t ha-1 FYM was applied in both seasons. The experimental study suggests that long-term FYM use enhances soil properties and productivity in semi-arid regions.