The aim of this study was to investigate the effect of lavender oil inhalation on labor pain among parturient women. Methods: A quasi-experimental trial was carried out at Labor and Delivery Unit of Mansoura University Hospital-Mansoura City on 250 parturient women in the active phase of the 1st stage of labor, who were selected by purposive sampling technique. They were free from any medical and obstetric problems, age between 20-35 years, with single viable fetus, occiptoanterior position and gestational age from 37 to 42 weeks. They were divided into either control or intervention group 125 per each group. The intervention group: inhaled two drops of 2% pure Lavender oil while the control group inhaled two drops of placebo oil. Pain score were measured by Numeric Pain Intensity and FLAAC Scales just before, immediately and after 30–40 minutes after oil inhalation. Results: pain level of the intervention group was lower than that of the control. Recommendation: the study suggests that lavender oil should be integrated into care provided during 1st stage of labor. Conclusion: lavender oil inhalation associated with lower pain level during the 1st stage of labor.