The study showed that temperature had an important effect both on the resistance of Pinus yunnanensis and on the growth and virulence of Leptographium yunnanense, a pathogenic fungus associated with Tomicus piniperda attacking Pinus yunnanensis, which would result in the competence variation between them: at lower (< 10 degrees C) and higher temperature(> 30 degrees C), the growth and virulence of L. yunnanense were inhibited, while at 15 degrees C-30 degrees C, the resistance of Pinus yunnanensis was relatively weaker, indicating that in warmer climates, the growth and virulence of L. yunnanense were relatively strengthened, but the resistance of Pinus yunnanensis was relatively weakened.