We have investigated the distribution of two_dimensional granular flow in inclin ed channel and the distribution of the density of granular flux (ξ=ρ·ν) near the rough boundary walls. The results showed that the transverse distributi on of the density of granular flux is symmetric about the channel center, and th ere exists a strong extremum near the wall; the distribution of the density of g ranular flux near the walls is nonlinear with increasing inclination. In this paper, we turn attention to the effect of channel width on the distribution of the density of granular flux. There is a critical channel width for the distribu tion of the density of granular flux. In our experimental condition, the critica l width is 700mm (Wc=70d,d being the granular diameter), and there i s a weak extremum in the curve of the density of granular flux distribution when the channel width is in the range from 70 to 80d. When the channel width is smaller than the critical width, the density of granular flux can be expressed by ξ∝(sinθ)α with,032≤α≤085 the value of α is related with the channel width.