The up-conversion luminescence of rare-earth ions is an important fundamental research for understanding the multi-photon excitation processes and up-conversion luminescence mechanism. The up-conversion luminescence control of Dy3+-doped glass are investigated theoretically and experimentally by using square wave modulated femtosecond pulse as excitation light source. Results show that up-conversion luminescence has different control efficiency with the higher or lower laser intensity. The physical control mechanism is further investigated by considering the higher-order multi-photon absorption process, and the up-conversion luminescence multi-photon absorption includes two-photon and four-photon absorption process. The relative weight of four-photon absorption in the whole excitation process increases with increasing of laser intensity. Due to the destructive interference between two-photon and four-photon transition pathways, up-conversion luminescence exhibits different control behaviors at different laser intensity. At high laser intensity, the observation of higher-order multi-photon absorption processes in rare earth ions can provide a clear physical picture for understanding the up-conversion luminescence mechanism, and a new way for tuning the up-conversion luminescence.