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The rapid development of global industry has led to the generation of large quantities of industrial waste, resulting in inefficient resource usage and environmental contamination. To improve the utilization of industrial waste, this study developed ultra-high-performance geopolymer concrete (UHPGC) by incorporating ground granulated blast furnace slag (GGBS), steel slag, silica fume, quartz sand, and steel fiber. Furthermore, the study explores the mechanical properties, durability, microstructural characteristics, and environmental benefits of UHPGC of steel slag (0 %, 10 %, 20 %, 30 %, and 40 %) and steel fiber (0 %, 1 %, 2 %, and 3 %) contributions. Results show that as the amount of steel slag increased from 0 % to 40 %, the flowability increased by 25.0 %, while compressive and flexural strengths decreased by 15.9 % and 30.1 %, respectively. With an increase in steel fiber dosage from 0 % to 3 %, flowability decreased from 222 to 162 mm, but mechanical strength gradually increased. The steel slag exhibited excellent durability properties after 300 freeze-thaw cycles and 18 sulfate attack cycles when the steel slag dosage was 40%. The compressive strength and the relative dynamic modulus of elasticity remained at 84.8 MPa and 75.1%, respectively. Microscopic analysis revealed that all specimens formed relatively dense microstructures with few pores and produced a large amount of gel, contributing to the enhanced durability of UHPGC. However, increasing the dosage of steel slag resulted in a gradual increase in the diffraction peaks of chromite (Cr 2 O 4), indicating an increase in unreacted steel slag. Steel fibers significantly improved the mechanical strength and durability of UHPGC. GGBS, steel slag, and steel fibers were the major environmental factors, particularly in terms of GWP and PED. The development of UHPGC using industrial waste slag as raw material can significantly promote the extensive utilization of steel slag in concrete and contribute to environmental sustainability. [Display omitted] • The steel slag improves the flowability, sulfate resistance, and freeze-thaw resistance of UHPGC. • Steel fiber improves the mechanical strength, sulfate resistance, and freeze-thaw resistance of UHPGC. • All the UHPGC have formed relatively dense microstructures with few pores. • GGBS and steel slag cooperate to promote the formation of late-stage C-S-H gel. [ABSTRACT FROM AUTHOR]