The life cycle of bridges, including its construction, maintenance, and disposal, emits carbon dioxide, but it is important for sustainability to minimize the carbon emission. Timber can absorb carbon dioxide during growth, reducing carbon emissions in construction. However, structural timber must have high and stable strength. Glulam (Glue laminated timber) achieves relatively higher and more stable strength than the solid wood, so it is increasingly being used as structural members for bridges. Recent studies aimed to increase the bending strength of the glulam to apply it to bridges with more heavy traffic. However, reinforcement with steel may increase the carbon emission and the weight of the beam. Therefore, this study aims to increase the bending strength of glulam beam with Basalt-Bioplastic FRP. Basalt fiber is made from basalt rocks and emits much less carbon dioxide than steel or Carbon FRP (CFRP). Bioplastic is the bio-based plastic which does not use petroleum-based materials. This study uses FRP which use the basalt fiber as the reinforcing fiber and the unsaturated polyester containing 26% bio-based plastic. The Basalt-Bioplastic FRP plate was inserted into the glulam beam on upper and lower sides, reinforcing its bending strength with the minimum carbon emission. This study first conducted material test of Basalt-Bioplastic FRP. The results showed that Basalt-Bioplastic FRP has almost the same tensile strength with Glass FRP (GFRP), which made Basalt-Bioplastic FRP reliable material for structural reinforcement. Secondly, the four-point bending tests were conducted with the glulam specimens with 2 m in span length. Two types of the specimens were prepared: unreinforced specimens and reinforced specimens with the Basalt-Bioplastic FRP. The four-point bending test on three specimens for each types revealed that the reinforced specimens had much higher bending strength than the unreinforced specimens. Moreover, the calculation of carbon emissions for each type of reinforcement, including steel, CFRP, and Basalt-Bioplastic FRP, revealed that the proposed reinforcement achieves both bending reinforcement and a minimal increase in carbon emissions.