This paper studies supervisory control of periodic event-triggered control (PETC) systems based on the construction of symbolic abstractions. To this end, we first construct symbolic abstractions for PETC systems, and establish feedback refinement relation from the PETC system to its symbolic models. Here, the constructed symbolic models are represented by the form of discrete event systems (DESs), including extended finite state machines, finite state machines, and classic DESs. With the constructed symbolic models, we study the supervisory control of PETC systems to achieve the desired specification. Since the constructed symbolic models are nondeterministic, we first transfer the symbolic models into deterministic versions, and then verify the existence of the supervisor. Finally, the obtained results are illustrated via a numerical example. Copyright (C) 2020 The Authors.