Abstract: In order to study the variation of temperature field and horizontal frost heaving force during the one-dimensional freezing and melting process of loess with different water content, the one-dimensional freezing and melting test under closed system was carried out on the loess from Lanzhou Area. The results show that the cooling process of the soil can be divided into four stages. The temperature drop rate of the soil at each depth is faster when the temperature is frozen. When the temperature drops to 0.4 ℃, the cooling curve shows a turning point, and the depth of the soil decreases. A plateau that is nearly parallel to the abscissa; the temperature of the soil at each depth is slower at the late stage of freezing. The maximum horizontal frost heaving force changes little along the soil depth, then increases to the maximum and finally decreases. The maximum value of horizontal frost heaving force changes obviously with the water content. The higher the water content is, the greater the horizontal frost heaving force is, while the other values are less affected by the water content. The maximum value of horizontal frost heaving force appears at the relative depth of 0.6 to 0.8.