Background Dignity is a vitally important aspect of the lives of advanced cancer patients. We conducted a systematic review and meta-analysis of the effectiveness of dignity therapy in this patient population. Methods We searched for randomized controlled trials comparing dignity therapy versus standard care for patients with advanced cancer in five comprehensive databases (March 2019), two clinical trial registries and one gray literature database (August 2019). The quality of the studies was assessed using the risk of bias tool recommended by the Cochrane Handbook Version 5.1.0. We used GRADE approach to assess the certainty of evidence. Meta-analysis was performed with RevMan version 5.3. Outcomes of interest included anxiety, depression, dignity-related distress and quality of life (QoL). Results Ten trials evaluating 904 patients (control, 449; experimental, 455) were identified. Six trials included patients with different types of advanced cancer, and four trials included patients with a single advanced cancer (lung cancer [20%], breast cancer [10%], and hepatocellular carcinoma [10%]). Compared with the standard care, dignity therapy decreased the score of anxiety, depression, and dignity-related distress of the advanced cancer patients (SMD = -1.07, 95% CI: [-1.57, -0.58], p < .05; SMD = -1.31, 95% CI: [-1.92, -0.70], p < .05; MD = -7.30, 95% CI: [- 12.04, - 2.56], p < .05). In addition, no significant differences were found in the patient's QoL (p > .05). Conclusion Very low certainty evidence demonstrated that dignity therapy might be a promising treatment, especially in reducing anxiety and depression in advanced cancer patients.