Inst High Energy Phys, Beijing 100049, Peoples R China
; CCAST, World Lab, Beijing 100080, Peoples R China
In this note, we calculate the branching ratio and CP asymmetry parameters of B-s->pi rho in the framework of perturbative QCD approach based on k(T) factorization. This decay can occur only via annihilation diagrams in the standard model. We find that (a) the charge averaged Br(B-s->pi(+)rho(-)+pi(-)rho(+)) is about (9-12) x 10(-7); Br(B-s->pi(0)rho(0)) similar or equal to 4 x 10(-7); and (b) there are sizable CP asymmetries in the processes, which can be tested in the near future Large Hadron Collider beauty experiments (LHC-b) at CERN.