A quantum-computing threats surveillance system for use in quantum communication environments is a quantum-surveillance technology which detects quantum computing threats based on free electron monitoring and entangled state measurement, and performs time-and-space analysis on quantum communication environments via making use of specific Fourier transforms, and then collaborate with a system of Lotka-Volterra competition models for variance analysis, so as to determine whether there is suspicious or potential quantum computing in a quantum communication environment. Furthermore, it can monitor different quantum-teleportation channels to achieve the effect of tracking specific quantum-computing behaviors for a long term.