Leaf functional traits can directly or indirectly reflect the adaptation strategy of plants to the environment, influencing their survival, growth, and reproduction. Until recently, there have been many studies on the relationship between leaf functional traits and environment, but most have used the single or mean value of the traits to represent one species, ignoring considerable intraspecific variations.Pinus tabuliformis is one of the main afforestation tree species in China, playing an important role in terrestrial ecosystems. Thus, the relationship between the leaf functional traits of P. tabuliformis and environmental factors could elucidate the relationship between intraspecific variations and environmental factors. The results of this study could provide a theoretical basis for better protection, development, and utilization of P. tabuliformis forests under global climate change. In the present paper, we analyzed the environment factors and distribution of eight leaf functional traits of P. tabuliformis in its natural distribution range, including leaf length (LL), leaf thickness (LT), specific leaf area (SLA), leaf dry matter content (LDMC), stomatal density (SD), leaf nitrogen concentration (LNC), leaf phosphorus concentration (LPC), and leaf carbon concentration (LCC), from leaves collected in Inner Mongolia, Liaoning, Beijing, Shanxi, Shaanxi, Ningxia and Qinghai Provinces, from June to September 2014. The results showed that 1) The leaf functional traits of P. tabuliformis showed significant intraspecific variations, and the variation coefficient was between 4.82% and 25.85%. The traits, except the LCC of annual leaves, showed significant differences between different research sites (P < 0.05), the intraspecific variation of LPC was the highest (23.29% for annual leaves and 25.85% for perennial leaves), and the intraspecific variation of LDMC was the lowest (5.91% for annual leaves and 4.82% for perennial leaves). 2) There were significant correlations between the leaf trait and the longitude and latitude (P < 0.05). LL, LT, SLA, SD, and LNC of P. tabuliformis leaves exhibited a weak longitude distribution pattern, and LT, SD, and LNC exhibited a weak latitude distribution pattern. The combined effect of changing hydrothermal conditions along longitude and latitude and strong local effects could contribute to the formation of these patterns. There was also significant variation among different individuals at the same site, suggesting large local effects, which could weaken the longitude and latitude distribution pattern on the large scale, leading to a small R value (0.05 < R² < 0.3). 3) The pattern of leaf functional traits was affected by various environmental factors, and each leaf trait of P. tabuliformis was affected by several factors. Further, the main controlling factors of different traits were different; the controlling factors of annual and perennial leaves were different in some traits. In the present study, we found that the LL was mainly affected by the mean annual precipitation and altitude, LT was mainly affected by the mean annual temperature and volumetric soil water content, SLA was mainly affected by the mean annual precipitation and soil nitrogen content, LDMC was mainly affected by water factors, SD was mainly affected by altitude, LNC was mainly affected by altitude and water factors, and LPC was mainly affected by soil phosphorus content.