The species diversity and community stability of gap and non-gap stands in Jinyun Mountain were studied by using species richness index(dGL), Shannon-Weiner index, Pielou evenness index(J), Simpson index(D), ecological dominance(lambda), evenness-dominance-abundance index(Z) and community dominance(C). The results showed that the dGL, H', J and D calculated by individuals numbers in gap are 12.14, 4.62, 0.70, 13.32, respectively. Shrub layer plays a greater role than other layers. The corresponding indices in non-gap stand are 6.32, 3.74, 0.66 and 8.16, respectively, which were lower than those in gap. Species diversity indices of the community were far higher in gap than in non-gap. However, ecological dominance and community dominance in gap were smaller than those in non-gap significantly. It suggested that species diversity of the community increased, and community stability decreased, due to the existence of gap formed by natural or human disturbance.