In the present study an experimental investigation is carried out to predict the performance of ground source heat pump systems with using different soil type under Karabuk prevailing conditions. A series of experiments were conducted on designed and produced experimental test rig. This study examines the effect of five different soil types on the performance and energy consumption of a heat pump. The experimental analysis showed that the evaporator capacity provided by sand was 46% and 42% higher than the capacity provided by red soil at the air-flow rates of 0.087 kg/s and 0.015 kg/s, respectively. In terms of the condenser capacity, sand provided 46% and 30% higher capacity than red soil at the air-flow rates o 0.087 kg/s and 0.015 kg/s, respectively. On the other hand, red soil consumed 8% and 6% less energy than sand at the air-flow rates of 0.087 kg/s and 0.015 kg/s. the capacities provided by other soil types and their energy consumption ranged between these values. In terms of the COP values, red soil provided 6% higher performance than sand and humus soil at the air-flow rates of 0.087 kg/s and 0.015 kg/s. The performance values obtained with other soil types ranged between these values.