Objective: To evaluate the efficacy in smoking cessation and safety of 2 and 4 mg nicotine mint lozenges in Chinese adult smokers. Methods: This was a multicenter, randomized, stratified, double-blind, placebo-controlled, parallel-group study. The low-dependence stratum included 483 smokers (241 randomized to active 2 mg nicotine lozenge and 242 to placebo lozenge). The high-dependence stratum included 240 smokers (120 randomized to active 4 mg nicotine lozenge and 120 to placebo lozenge). The primary endpoint was successful smoking cessation at 6 weeks postquit, defined as continuous abstinence from smoking for the 28-day period up to and including the 6-week visit (verified by CO measurement). Cochran-Mantel-Haenszel tests were performed to compare quit rates between active nicotine and placebo separately for the high-dependence and low-dependence strata. Results: The primary analysis showed that in the low-dependence (2 mg) stratum, 59 subjects (24.5%) of 241 in the active nicotine group and 52 subjects (21.5%) of 242 in the placebo group were successful quitters (P = .3851). In the high-dependence (4 mg) stratum, 37 subjects (30.8%) of 120 in the active nicotine group and 24 subjects (20.2%) of 119 in the placebo group were successful quitters (P = .0565). Conclusions: The 4 mg nicotine lozenge provided a directionally significant improvement in smoking cessation rates compared with placebo in Chinese adult smokers with high nicotine dependence for the primary endpoint. The 2 mg nicotine lozenge provided higher, but nonsignificant, smoking cessation rates than placebo. Both nicotine lozenges were generally well tolerated in Chinese adult smokers.