We study the competition between dispersion and absorption of doubly-dressed four-wave mixing(DDFWM)and dressed six-wave mixing.In the case of weak coupling fields limit,we find DDFWM signal is affected by destructive interference between four-wave mixing(FWM)and six-wave mixing as well as constructive interference between FWM and eight-wave mixing.By analysing the difference between two kinds of doubly dressing mechanisms (parallel cascade and nested cascade)in this opening five-level system,we can further understand the generated high-order nonlinear optical signal dressed by multi-fields.