Abstract: Recycled brick aggregate geopolymer concrete (RBGC) is a sustainable building material with great potential, but there are few studies on the performance of RBGC before and after high temperatures. Firstly, the influence of the amount of cementitious material and the type of coarse aggregate on the axial compression constitutive model of geopolymer concrete was explored. It is found that with the increase of cementitious material, the compressive strength, split tensile strength, elastic modulus and peak compressive strength of RBGC decrease. The change amplitude of strain is smaller than that of ordinary aggregate geopolymer concrete (NAGC). The linear section of the rising section of the stress-strain curve of RBGC is longer, and the stress decreases faster in the falling section. Secondly, the mechanical properties of RBGC and NAGC after high temperature were studied. At 800℃, the strength and stiffness loss of RBGC are 22.1% and 18.3% smaller than that of NAGC respectively. And it is found that RBGC shows better high temperature resistance, and different models should be used to calculate the mechanical performance indicators of the two concretes. This is because the temperature expansion coefficient of brick aggregate is close to that of geopolymer mortar, and the internal temperature gradient of RBGC is small at high temperatures. Finally, by correcting the shape parameters of the descending section, the stress-strain relationship model of RBGC and NAGC before and after high temperature is determined, and the model is in good agreement with the test results.