This study systematically reviewed randomized controlled trials (RCT), published in English or Chinese, investigating the effect of complementary and alternative medicines (CAM) on significant insomnia/poor sleep quality and accompanying depression and/or anxiety symptoms. A meta-analysis was completed by calculating within-group effect size (ES) of each CAM treatment on sleep, depression and/or anxiety measures. Moderating analyses of study quality, language, treatment duration and presence of physical diseases were conducted to evaluate their impact on ESs. Between-group ES of CAM (vs. non-specific/placebo controls) were computed among high-quality studies. From an initial pool of 5047 articles, a total of 72 studies were included in the meta-analysis (44 in English; 28 in Chinese). All CAM modalities yielded significant, moderate to large effect sizes on sleep, depression, and anxiety symptoms yet with high heterogeneity. Significant between-group differences on sleep measures were found only between mindfulness-based treatment and non-specific/placebo controls. Chinese literature are associated with larger ESs. Future study should examine the presence and nature of the active components in different CAM approaches.