Abstract: The Puguang Gasfield is one of the biggest gas reservoir in northeast Sichuan Basin, and it is con-trolled by lithology and structures. This paper studies the characteristic of lithology, reflection coefficients and the characteristics of seismic reflection. The results indicate the reservoir characteristics and physical property of T₁f_1-2 is better, its reflection coefficient is bigger than T₁f₃, and the characteristics of bright spots and dark spots are obvious in Puguang Gasfield. The effects of deploying wells according to seismic reflections are good.