As the largest amount of biomass residues produced from the palm oil industry, the oil palm frond (OPF) is a promising solid fuel resource for gasification. However, the difficulty in processing OPF into solid fuel may affect the solid fuel production rate and consequently the gasifier operation. To ensure a continuous gasifier operation unaffected by the shortage of OPF fuel, empty fruit bunch (EFB), palm mesocarp fiber (PMF) and palm kernel shell (PKS) were introduced as a pairing fuel with OPF for co-gasification. The potentials of the fuel mixes and the effects of the fuel blending ratio on syngas higher heating value, specific syngas yield, carbon conversion efficiency and cold gas efficiency were studied. The experiments concluded that all fuel mixes of all blending ratios satisfied all the syngas quality indicator requirements and that all the tested fuel mixes can be utilized for downdraft co-gasification to produce results similar to the downdraft gasification of 100 OPF. © 2018 The Authors, published by EDP Sciences.