Abstract: In this paper, the effects of molding pressure, water-to-binder ratio and load-holding time on the flexural strength and fracture energy of premixed casting GRC were studied. The results show that the effects of various factors on the flexural strength and fracture energy of GRC are different. The higher the molding pressure, the higher the flexural strength and the lower the fracture energy of GRC. Under pressure forming conditions, the flexural strength of GRC does not change significantly with the increase of water-to-binder ratio, but the fracture energy increases greatly with the increase of water-to-binder ratio. With the prolongation of load-holding time, the flexural strength of GRC increases slightly, but the fracture energy changes little. The fracture energy of GRC decreases with the increase of molding pressure when the glass fiber content is different. The empirical formula obtained by fitting the experimental data can better reflect the relationship between GRC fracture energy ( of different glass fiber content and pressure-free GRC fracture energy ( ) and molding pressure (F) under the experimental conditions.