There is a problem that it is difficult to express and understand the PQKD (Parallel Quantum Key Distribution)
processes with quantum entanglement states for its novelty and complexity. To solve this problem, the control idea is
adopted to model the PQKD system for the design of the corresponding PQKD schemes using the tool of UML (Unified
Modeling Language). The results of demon animations by the UML models show that the dynamic processes of PQKD
with entangled states can be illustrated more clearly and intuitively than before, while the PQKD control system remains
the advantage of unconditional security. These models are important to develop large-capacity long-distance PQKD.