Background: The World Health Organization states that mothers during labor and delivery should be supported by people with whom they feel comfortable, because one of the non-pharmacological methods of relieving labor pain is the continued support of midwives in labor. The primary objectives of this study were to determine the effect of continuous midwifery support in labor on delivery experience and self-esteem of nulliparous women 6 weeks after delivery.Methods: This randomized controlled trial was performed in 2021 on 70 pregnant women admitted to the delivery ward who met the inclusion criteria. Participants were randomly allocated to two groups through balanced block randomization with a block size of 4. Participants completed a demographic and midwifery information questionnaire before entering the study. In the intervention group, in addition to routine labor care, the researcher was present at the mother's bedside and was present with the mother continuously throughout the labor and up to 2 hours after delivery and provided the necessary support. The control group received only routine labor and postpartum care. Six weeks after delivery, participants in both groups were contacted to complete the CEQ and Rosenberg self-esteem questionnaires. Finally, data were collected and analyzed. Significance level was considered 0.05.Results: By controlling the effect of duration of the first and second stages of labor as potential confounders, the mean (sd) of childbirth experience 6 weeks after delivery was 70.92 (7.07) in the intervention group and 59.69 (7.08) in the control group, and this difference was statistically significant (p <0.001). The amount of effect size indicates a very strong effect of the intervention on improving the childbirth experience (Cohen’s d = 1.69; 95% CI: 1.12, 2.26). Comparison of the mean of maternal self-esteem showed that this rate in the intervention group was 2 scores higher than the control group and this difference was statistically significant (p = 0.05). Cohen's d indicates the average effect of intervention on mothers' self-esteem score (Cohen's d = 0.56; 95% CI: 0.06, 1.05).Conclusions: Continuous support of the midwife in labor and up to 2 hours after delivery can lead to a better childbirth experience and increase the mother's self-esteem up to 6 weeks after delivery.Trial registration: IRCT ID: IRCT20201102049233N1, First Registration date: 2021-06-04