Weed increase reduces crop yields, while chemicals applied to control weed have adverse environmental impacts. Thermal control has a less negative effect on the environment and health of consumers compared to chemical methods. After construction, the flame weeding efficiency of this method for eliminating near-row weed at three speeds of drive and three different amounts of liquid gas consumption was evaluated. The flame weeding manufactured and connected to the back of an offset tractor and navigation system. The flame weeding had a sidewall that prevented the flame from directly touching crop plants inside the row. Flame weeding were performed based on split-plots and on randomized complete block design with two factors of movement speed at three levels of low (3 km/h), medium (4 km/h) and high (5 km/h) and liquid gas consumption does at three levels of low (3 km/h), medium (5 km/h) and high (7 km/h). The results in both sugar beet and corn showed the interactive effects of two speed and amount consumption factors on each other. Weed control rates had varied considerably with flame treatment at different speeds and doses of liquid gas. With the increasing speed and decreasing liquid gas, the average weed control ratio decreased from 0.86 to 0.1. needle leaf weed control ratio in all cases is less than broadleaf weed. As the advance rate and the amount of liquid gas consumed decreases, the proportion of weed control declines substantially, and vice versa. This trend showed an inverse correlation between speed and liquid gas consumption factors.