Abstract: Background: Non-pharmacological pain-management approaches, including acupoint hot compress, may provide valuable support for women dealing with pain during the latent stage of labor, but the evidence supporting this effect is limited. We investigated whether acupoint hot compress reduced labor pain among primiparous parturients with planned vaginal delivery. Methods: We conducted a randomized controlled trial (RCT) at nine obstetric centers across China. Primiparous women aged 20-34 years, at 37-41 weeks' gestation with singletons and with planned vaginal delivery, were randomly assigned (1:1) to receive standard obstetrical care with acupoint hot-compress therapy or standard obstetrical care alone. The acupoint hot-compress therapy, involving the medial malleolus, plantar, and lumbosacral regions, was provided for parturients in the latent phase of the first stage of labor at (42±2) °C for 4 h, starting 1 hour after the onset of regular uterine contractions. The primary outcome measured was labor pain at 3 and 5 hours after the onset of regular uterine contractions, with labor pain at 1 hour used as the baseline. Pain intensity was assessed using the Visual Analog Scale and expressed as no pain (0), mild pain (range 1-3), moderate pain (range 4-6), or severe pain (range 7-10). The secondary outcomes were the duration of the first, second, and third stages of labor, maternal blood loss quantified at 0 and 2 hours postpartum, and depression symptoms identified using the Edinburgh Postnatal Depression Scale (EPDS) within 48 hours postpartum, as well as newborn Apgar scores. All statistical analyses were based on the modified intention-to-treat (ITT) population. Results: Between April 2024 and May 2025, 580 women were randomly assigned to the acupoint hot-compress intervention group and the standard-care control group. Of the 564 women included in the modified ITT population, baseline characteristics were comparable between the two groups, with the exception of baseline labor pain. Compared with parturients in the control group, those in the intervention group who underwent acupoint hot compress from the latent phase of the first stage, had reduced labor-pain intensity (3 hours: odds ratios (OR) = 0.46, 95% confidence interval (CI) (0.31, 0.68), P<0.001; 5 hours: OR = 0.11, 95% CI (0.07, 0.18), P<0.001), after adjusting for baseline labor-pain intensity, and alleviation of postpartum depression symptoms (median EPDS score: 4.00 vs. 5.00, P = 0.009); while they had comparable labor duration, postpartum blood loss, and newborn Apgar scores. No adverse events were observed in either group. Conclusions: This RCT showed that acupoint hot compress, starting from the latent phase of the first stage of labor, could be considered as an adjunctive intervention for labor pain and postpartum depression for primiparous women with planned vaginal delivery, without effects on labor duration, blood loss, or newborn Apgar scores.