This study adopted oxygen lance technology to reduce NOx concentration for an industrial furnace. The parametric studies indicate the gaps and angles of oxygen lances. In this study, the gaps of oxygen lance are 680 mm and 410 mm, and the angles of oxygen lance are 25°, 30° and 45°. The experimental results showed that the NOx concentrations of flue gas can decrease more than 37% and the burner tile temperatures can decrease more than 90 ℃ after adopting oxygen lance for any gap and angle between 24% and 30% O2.