Ecological success under different environmental conditions and interactions among organisms may require plants to share certain common functional traits, allowing for the classification by plant functional type (PFT). The objective of this study was to explore the adaptation strategies of different PFTs and the change in number of species in each type along a vegetation restoration gradient in a forest-steppe zone in the Yanhe River catchment, Shaanxi, China. We placed emphasis on PFT dynamics and variations during vegetation restoration of an abandoned farmland in this area. Our goal was to provide helpful information to better understand how plant adaptation strategies change as vegetation restoration progresses. This study used a spatial sequence approach instead of a temporal sequence one. We measured four leaf traits (thickness [LT], specific area [SLA], tissue density [LTD], and nitrogen concentration per unit mass [LN]) and three fine root traits (specific length [SRL], tissue density [RTD], and nitrogen concentration per unit mass [RN]) for each of the 39 species belonging to 16 families in 33 plant communities across five vegetation restoration stages in a forest-steppe zone in the Yanhe River catchment. All species were classified into one of the three PFTs based on the seven functional traits using cluster analysis. One-way analysis of variance was used to describe the variation among the PFTs. We then analyzed adaptation strategies for each PFT and compared the changes in the functional type composition along with the vegetation restoration stages. The results showed the following. (1) Based on the seven functional traits, which showed large variations across all 39 species, the plants were classified into three functional types (PFTI-Ⅲ). (2) Plants in PFT-Ⅰ had higher LTD and lower LT, LN, and RN; plants in PFT-Ⅱ had higher RTD, LN, and RN, and 39 species showed large variation. (3) Plants in PFT-Ⅰ had higher LTD and lower LT, LN, and RN; plants in PFT-Ⅱ had higher RTD, LN, and RN and lower SLA and SRL; and plants in PFT-Ⅲ had larger LT, SLA, and SRL and lower LTD and RTD. (4) According to the C-S-R triangle theories of Grime, PFT-Ⅰ, which invested more energy in defense and had an intermediate growth rate, adopted the "stress tolerance-ruderals" strategy. PFT-Ⅱ adopted the "stress tolerance-competitiveness" strategy, which allows survival in resource-poor environments by maintaining the nutrient balance in the body. PFT-Ⅲ devoted large quantities of nutrients to growth and belonged to the "competitiveness" strategy. (5) PFT-Ⅰ was dominant in all vegetation restoration stages and increased in prevalence across the vegetation restoration gradient (from 61% to 80%), while the percentage of PFT-Ⅱ decreased from 25% to 15% and that of PFT-Ⅲ from 14% to 5%. The dominant species within PFT-Ⅰ also changed over time. SLA of the dominant species in PFT-Ⅰ decreased markedly, and LN and RN of the dominant species in the early restoration period were bigger than in later stages. Although the nutrient content of the soil increased along the restoration gradient, the environment has not been sufficiently improved to eliminate stress during the 40 or 50 years of early vegetation restoration. Thus, PFT-Ⅰ, with adaptation strategies favoring stress tolerance over rapid growth, were dominant. These results may help guide species selection and restoration planning.