The study of forest fuel adjustment and control, and assessment of its impact, form the basis of fuel management, which is important for reduction of forest fires. Pinus tabulaeformis is a typical coniferous species in North China, and four 20m×20m sample plots were established in a P. tabulaeformis forest. Using field investigations and measurements, the distribution of forest fuel in the stand was analyzed, suitable fuel management activities, including pruning and cutting of shrubs, were conducted, and the effect of fuel management on the understory biodiversity and the photosynthetic attributes of the dominant shrub species were studied, comparing treated and untreated stands. Four different fuel treatments were used: CK, control; P1, Cutting shrubs; P2, Pruning (below 3 m) and cutting shrubs; P3, Pruning (below 3.5 m) and cutting shrubs. The results showed that: (1) The distribution of the P. tabulaeformis fuel load was highest in the 0-3 m layer (an average of 1053.94 g/m²), and included the most types of fuel. Fuel load decreased as height increased. (2) After the fuel treatments, the maximum net photosynthetic rate, light saturation point, light compensation point, and dark respiration rate of plants in the understory (the main species were Grewia biloba var. parviflora and Diospyros lotus) increased, while the apparent quantum efficiency was reduced. (3) The different fuel treatments altered the diversity of the understory community. Compared with the control stand, the species richness, species diversity, species dominance, and species evenness of the grass layer in the different fuel treatments increased. Thus, the diversity of the understory and physiological characteristics of the dominant species were affected by the forest fuel control measures. These findings provide a theoretical basis for the development of forest fuel treatments in the study area.