Abstract: OBJECTIVE To observe the effectivity and safety of epidural ropivacaine combined with dexmedetomidine in labor analgesia. METHODS One hundred and twenty nulliparous women were randomly divided into dexmedetomidine group and fentanyl group. After successful epidural puncture, maternals in dexmedetomidine group received epidural 0.1% ropivacaine 10 mL with dexmedetomidine 1 μg·mL^-1 in addition for labor analgesia, whereas maternals in fentanyl group received epidural 0.1% ropivacaine 10 mL with fentanyl 2 μg·mL^-1 in addition. The Ramsay scores(RSS) and visual analogue scale(VAS) scores, the mean arterial pressur(MAP), heart rate(HR) and pulse oxygen saturation(SPO₂) were recorded before labor analgesia(T₀), at 15 min after labor analgesia(T₁), at 60 min after labor analgesia(T₂), at the moment of complete cervical dilatation(T₃) and at the end of PCEA(T₄). Plasma epinephrine and norepinephrine concentrations in T₀ and T₂ were observed. Time of first and second stage of labor, forceps delivery rate, Apgar score 1 min after delivery were observed. The adverse reaction incidence of convulsion, hypotension, bradycardia, respiratory depression, nausea and vomiting, pruritus cutanea, excessive sedation, motor nerve block, fetal heart abnormality and eonatal Apgar score decreased were recorded too. RESULTS There were no statistically significant difference in RSS, VAS scores and SPO₂ in dexmedetomidine group and fentanyl group. Compared with the fentanyl group, the incidence of breakthrough pain were lower in dexmedetomidine group(P<0.05), and started late(P<0.05), had larger dilatation of uterine orifice at the beginning(P<0.05), the MAP at T₄ were significant lower(P<0.05). The HR at T₃ and T₄ were significant lower in dexmedetomidine group(P<0.05), the plasma catecholamine value at T₂ were significant lower(P<0.05), the incidence of nausea and vomiting, pruritus cutanea and excessive sedation were lower(P<0.05). There was no significant difference in the delivery status and neonatal Apgar scores between the two groups. CONCLUSION In labor analgesia, epidural ropivacaine combined with dexmedetomidine is more effective to treat breakthrough pain and the incidence of nausea and vomiting, pruritus cutanea and excessive sedation is lower.