Post-Tensioned Timber (PTT) frames combine high-strength tendons with heavy timber elements to create seismic low-damage or longer span timber structures. Although many aspects of structural performance, including seismic and long-term performance, have been investigated, the behaviour of beam-column connections in fire has not been studied. Since it is the ductile rocking beam-column connections that give this system its advantageous response, the behaviour of these connections is key to evaluating the full-structural performance in fire. This paper presents the results of an experiment of a simple PTT beam-column subassembly under an applied load and exposed to an ISO 834 Standard Fire. The connection decompressed after 3 min and the beam rotation increased exponentially until the applied moment was unable to be resisted at 20 min. Temperatures in the timber connection away from and at the connection are presented. Although the tendon force decreased from the effects of heating, the primary reduction in tendon force was due to crushing of timber under the anchorage.