To investigate the effect of nozzle and gum type on spray quality, drift, and efficiency of haloxyfop-R-methyl when applied with a drone (Agras MG 1P), a three-factorial experiment was conducted at the research field of Bu-Ali Sina University in the fall of 2023. The first factor included gum type (with and without guar and xanthan gums), the second factor included haloxyfop-R-methyl dose (0, 9.4, 18.9, 37.8, 56.7, and 75.6 g/ha), and the third factor included flat fan nozzle type (standard, anti-drift, and air-induction). Moisture-sensitive cards were placed in the center of the plot and 2 meters from the edge of the plot. In the center of the plot, the highest spray coverage (31.7%) was observed using anti-drift nozzle in the presence of xanthan gum. However, the highest droplet density (3.41 drops/cm2) was observed using standard nozzle in the absence of gum. However, the best spontaneous barley control efficiency was achieved by haloxyfop R-methyl using anti-drift nozzle in the presence of guar gum. Therefore, to control 50 and 90% spontaneous barley with this treatment, 7.7 and 31.0 g/ha haloxyfop R-methyl were required, respectively. No visible drift was recorded using air-induction nozzle with and without gum. With other nozzles, adding gums to the spray solution reduced the drift of spray droplets. Although the addition of gums to the spray solution reduced the spray coverage and density of droplets, contrary to expectations, it increased spontaneous barley control efficiency. This discrepancy is related to the water retention potential of the droplets by the gums.