The reindeer (Rangifer tarandus) has been a wildlife resource used extensively by local people across its range for thousands of years. In China, the reindeer occurs only in the northeastern part of the Great Xing'anling area in Inner Mongolia. The Owenki people in this area have long exploited the reindeer for its hide, meat, velvet antlers, and milk, showing its economic importance. However, the reindeer has fallen into the critically endangered status, with only about 800 left in its native range. There have been some publications addressing biological and ecological characteristics of the Chinese reindeer, but most of them have been anthropological and ethnological studies of anecdotal character. To date, there has been no study on the habitat selection of reindeer. To implement an in situ conservation program for increasing its population, it is critical to study habitat selection of the reindeer in China. The purpose of this paper is to present quantitative survey results of the reindeer's spring habitat selection in China and to explore the key factors influencing its habitat utilization. Thereby, implications for conservation measures to be implemented are discussed. In March and April of 2012 and 2013, habitat selection of the reindeer was surveyed in the Genhe area of northeastern China using line-transect surveys. A total of 23 habitat factors were measured and compared for 211 sample plots, in which 79 plots were designated as used-plots and 132 as non-used plots. The results indicated that reindeer in Genhe area preferred to select spring habitats at higher altitude ((957.27±1.68) m), with higher tree canopy ((32.84±2.72)%), tree density ((21.72±1.52) per 400 m²), increased ground-plant cover ((85.06±1.03)%), stump quantity (6.81±0.45), and fallen-wood quantity (5.73±0.54), but with lower shrub canopy ((57.95±2.79)%), withered-grass cover ((33.11±2.79)%), tree height ((9.58±0.27) m), and shrub height ((59.85±2.69) cm), compared to the non-used habitat plots. Moreover, the reindeer also selected habitats with intermediate to low slope (67.09%) on the south and west slopes (77.21%), which were located mainly in conifer forests (68.35%) and provided relatively good concealment (82.28%), more protection from wind (64.56%), relative proximity to water sources (< 1000 m, 94.94%), and were farther away from human disturbance (<1000 m, 87.34%). The principal component analysis showed that slope position, tree characteristics (tree height and tree diameter at breast height), food abundance (shrub cover, number of fallen wood, and stump number), snow characteristics (snow depth, snow cover, and tree canopy), disturbance intensity (distance from human influence), and vegetation type (slope aspect and vegetation type) were most important in determining the spring habitat selection of the reindeer. In summary, the results indicated that the reindeer's habitat selection in the spring was a multidimensional process through which the reindeer could adapt to local ecological conditions of temperature, food abundance, shelter, water supply, and ground cover. Furthermore, the reindeer in China has not yet been domesticated, and it is necessary to introduce conservation methods for its protection since it is critically endangered species.