Background Coblation is a novel technique in respect of treating idiopathic trigeminal neuralgia. We aimed to identify the efficacy and complications between radiofrequency thermocoagulation (RFT) and coblation for V2/V3 idiopathic trigeminal neuralgia (ITN) and investigate the risk factors associated with postoperative facial numbness. Methods: We retrospectively reviewed our cohort of 292 patients who had undergone RFT or coblation for V2/V3 ITN. The characteristics of the baseline were collected before surgery. Pain scores, the degree of facial numbness and other complications were evaluated at discharge and 1 month, 3 months, 6 months and 12 months after surgery. Results Postoperative pain intensity was apparently alleviated in both groups. The initial and 12-months remission rates were 94.0 and 75.3% in coblation group compared with 96.9 and 78.4% in RFT group (P = 0.462, P = 0.585). The degree of postoperative facial numbness tended to be more severe in RFT group at discharge, 1 month, 6 months and 12 months (P = 0.006, P = 0.026, P = 0.004, P = 0.003). Factors significantly associated with more severe facial numbness were procedure of RFT (OR = 0.46, 95%CI: 0.28-0.76, P = 0.002), history of previous RFT at the affected side (OR = 2.33, 95%CI: 1.21-4.48, P = 0.011), and ITN with concomitant continuous pain (OR = 0.36, 95%CI: 0.18-0.71, P = 0.004). Conclusion Coblation could reduce the degree of postoperative facial numbness for ITN, and the efficacy was no less effective than RFT. History of previous RFT at the affected side, procedure of RFT, ITN with concomitant continuous pain was identified as significant factors of the development of postoperative facial numbness.