Background: Pain control is considered as the key issue in modern midwifery. Along with medical painkillers, reflexology is viewed as a non-medical and noninvasive method. Hence, we aimed to investigate the effect of reflexology on the intensity of pain and length of labor. Materials and Methods: In this clinical trial, participants included 240 Iranian primiparous women with term and singleton pregnancy. Having a 3-4 cm cervical dilatation once they visited the hospital. Through a convenient sampling method, they were selected and then randomly divided into two groups. In the intervention group, reflexology was performed, and the intensity of pain during the active phase of labor along with the length of labor in the active phase was measured by visual analog scale (VAS) and compared with the control group. Data were analyzed using descriptive statistics, t-test, and Mann-Whitney U-test. Result: Data analysis showed a statistically significant difference between the intensity of pain in the 5-7 and 8-10 cm dilatation in the two groups (P=0.01). Moreover, the labor length in the active phase was found to be significantly shorter in the intervention group (P<0.001). Conclusion: It appears that reflexology can lead to a reduction in the pain and length of labor. Therefore, through instructing this technique, a goal of midwifery, which is reducing labor pain and its length can be achieved. Keywords: Reflexology, Labor Pain, Labor Length, Primiparous Women