<p>This study investigates the mechanical and structural performance of synthetic steel fiber-reinforced geopolymer concrete (GP) through rheological, compressive, flexural, and ductility tests. The effect of fiber inclusion (0%, 1.0%, 1.50%, and 2.0%) on the slump, compressive strength (CS), stress-strain behavior, and energy absorption capacity was examined. The results indicate that the addition of synthetic steel fibers reduced the slump values, with the plain GP exhibiting the highest workability. The incorporation of fibers enhanced the CS by up to 71% equated with the control specimen, with the optimal performance observed at 1.50% fiber content. However, beyond this limit, a reduction in CS was noted due to casting difficulties. Load-displacement analysis depicted that the fiber reinforcement expressively improved the axial stiffness and post-peak behavior, with the 1.50% fiber-reinforced specimen exhibiting the largest load-displacement curve. Stress-strain curves highlighted an increase in elastic responses and crack bridging capacity, delaying failure. In flexural tests, specimens reinforced with 1.50% fibers showed superior energy absorption and post-peak performance, whereas those with 1% fiber content displayed brittle failure similar to the control mix. The energy absorption capacity of GP improved by up to 223% with fiber reinforcement, demonstrating the potential of synthetic steel fibers in enhancing the toughness and durability of GP composites. These findings suggest that fiber-reinforced GP can be effectively used in structural applications requiring enhanced ductility and energy dissipation characteristics.</p>