For many species pelage characteristics undergo seasonal variations. Likewise, intraspecies variation of pelage characteristics can occur according to location and habitat characteristics for some mammals. Such variations can substantially affect the function of the pelage. In cold environments the pelage plays a particularly key role in the survival of many mammals. Differing pelage characteristics may suggest a number of different strategies of pelage insulation. In this analysis, we explore the relationship between pelage characteristics and pelage insulation value for the captive arctic fox (Alopex lagopus) in the Mohe area of Heilongjiang Province located at the far north of China. Fourteen pelage parameters were measured. Results indicated that hair density was (26802.8±4499.8) hairs per cm2. The length of guard hairs, undercoat hairs forming the top layer and undercoat hairs in the base layer was (6.08±0.64) cm, (5.19±0.28) cm, and (294±0.30) cm respectively. The diameter of the root of guard hairs, undercoat hairs forming the top layer and undercoat hairs in the base layer was (66.33±6.55) μm, (10.14±0.67) μm, and (9.17±1.01) μm respectively. The diameter of guard hairs, undercoat hairs forming the top layer and undercoat hairs in the base layer was (113.63±492) μm, (22.22±1.64) μm, and (20.41±1.74) μm respectively. The maximum cross-sectional area of the hair bundle was (1.09±0.26 ) ×104μm2. The arctic fox had two layers of undercoat hair. The length of guard hairs was not significantly correlated with either length of the undercoat hairs forming the top pelage layer or with length of the undercoat hairs in the base layer. The length of the undercoat hairs forming the top layer was close to that of the guard hairs. However, the length, hair root diameter and hair diameter of undercoat hairs at the base layer were shorter and smaller than undercoat hairs forming the top layer. Undercoat hairs at the base layer filled in the space between guard hairs and undercoat hairs forming the top layer. At the same time, the maximum cross-sectional area of compound hair follicles was slightly correlated with hair root diameter, hair number per bundle, and hair bundle density. Hair density was not significantly correlated with hair root diameter, or with hair diameter, or with hair number per bundle, or with total maximum cross-sectional area of the compound hair follicles per mm2. However hair density was negatively correlated with the maximum cross-sectional area of the compound hair follicles (P<0.05) and positively correlated with hair bundle density (P<0.01). Pelage density (pelage insulation value) of the arctic fox was not increased by having a smaller hair diameter or increased numbers of hairs, but by varying the distribution of the hair bundle density and the maximum cross-sectional area of the compound hair follicles. We presume that the insulation value of the arctic fox pelage was enhanced by increasing the volume and retention of air within the pelage in two ways. First, hair density was increased by variable hair distribution patterns over the skin. Second, the presence of two layers of undercoat hairs with medullae changed the spatial structure of the pelage. These two strategies help the arctic fox adapt to the cold climate in the high latitude areas of China.