In this study, the effects of equivalence ratio and biochar particle size on high heating value, gas composition, carbon conversion, and gas production from the empty fruit bunch biochar were experimentally investigated in a fluidized bed reactor. Equivalence ratio varied from 0.1 to 0.34, while the size varied from 0.2 mm ≤ s ≥ 1 mm. It was observed that the syngas production increased as the air flow rate increased until equivalence ratio was equivalent to 0.24 and finally decreased with increasing equivalence ratio. In addition, the high heating value of syngas also decreased as equivalence ratio increased. The increase in the particle size from 0.2 mm ≤ s ≥ 1 mm decreased the H2 yield from 34.75 to 25.3%, and decreased the overall syngas production and high heating value. The produced syngas revealed a high heating value in the range of 22.6–52.9 MJ/KG. Meanwhile, the maximum char to gas conversion efficiency achieved was 80.2%. A hydrogen-rich gas was successfully produced through air gasification at...