Early amniotomy is one of the main interventions to enhance the labor progress and prevent dystocia in pregnant women. However, the efficacy of amniotomy has not been approved via labor-related indices and outcomes and has remained a subject for debate and future research. The present study was conducted to evaluate the effect of early amniotomy on labor indices and outcomes in nulliparous women. This randomized clinical trial was performed on 151 singleton pregnant women who were referred to Besat Hospital in Sanandaj, Iran, from March 2016 to March 2018. Participants were randomly divided into an early amniotomy (EA) group and a control group. Duration of the first and second phases of labor, corioamionit, dystocia rate, Apgar score at the first and fifth minutes, prolonged labor and post-partum haemorrhage were evaluated and compared between the two groups. Data were recorded in a checklist and analysed using SPSS Version 23. The p value <0.05 was considered significant. Results showed that labor indices such as duration of the first and second phases, Apgar score one and five minutes after delivery and frequency of prolonged labor, foetal distress and postpartum haemorrhage were significantly improved in patients of the early amniotomy group, compared with the control group (p≤0.05). Early amniotomy significantly decreased the total labor duration without significant increase in the rate of maternal and neonatal complications.