Abstract: Usage control is one of the next generation technologies that protect the digital resources.Petri net can specify distributions，concurrencies and synchronizations of usage control and is the effective technology for describing and analyzing usage control model.This paper defines the polices of authorization control model and expresses them in Petri nets.It is verified that the representations are soundness and completeness.At last，the author shows the flexibility and expressive capability of based-Petri UCONA by an example.

Key words: usage control, Petri net, access policies, soundness, completeness

摘要： 使用控制是最有希望的下一代数字资源使用保护技术，Petri网能够描述使用控制模型的分布、并发、同步等特征，是表达和研究使用控制模型的有效技术。定义了授权控制模型的访问策略，然后采用Petri网进行了表达，证明了Petri网表达授权访问策略的正确性，最后通过示例说明了Petri网表示的表达能力。

关键词: 使用控制, Petri网, 访问策略, 合理性, 完整性