In this paper, based on a temperature dependent fracture surface energy model and the traditional Griffith fracture theories, a new temperature dependent fracture strength model for the ZrB2-SiC composites is developed. The combined effects of temperature, grain size, microflaw size and residual stress on the strength of ZrB2-SiC composites are included in the new model. According to the model, the temperature dependent fracture strength of materials can be easily predicted using some basic material parameters. The model is verified at different temperatures by comparison with experimental data of different ZrB2-SiC composites. Excellent agreement is obtained between predicted and experimental data of fracture strength of ZrB2-SiC composites. (C) 2015 Elsevier Ltd. All rights reserved.