The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. On this basis, an active dynamic pre-protection (ADPP) mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path (TPP) for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time.