In this talk I present the study of the decay modes B_s –> φ π^0 and B_s –> φ ρ^0 using Soft Collinear Effective Theory. I briefly give an introduction to Soft Collinear Effective Theory and discuss the importance of electroweak penguins in the decay modes B_s –> φ π^0 and B_s –> φ ρ^0. The branching ratios of these decay modes are so small in the SM and thus provide a test for new physics beyond SM. Please note that I will be at KEK only between Jan/07(Mon) and Jan/10(Thu). Pleae organize the seminar in this week.