CCAST, World Lab, Beijing 100080, Peoples R China
; CAS, Inst High Energy Phys, Beijing 100049, Peoples R China
; Chinese Acad Sci, Grad Sch, Beijing 100080, Peoples R China
; Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China
We carry out a theoretical and Monte Carlo study on the J/psi decays into omega pi pi and KK pi though intermediate subthreshold rho meson by using SU(3)-symmetric Lagrangian approach. It is found that the subthreshold rho contribution is not negligible and may have significant influence on partial wave analysis of resonances in these channels, especially near the omega pi and KK thresholds.