Introduction: People who stutter (PWS) often suffer from psychological difficulties in addition to stuttering symptoms. Recently, mindfulness and compassion interventions have been applied to PWS to ameliorate these difficulties. The present study aimed to systematically review the applications of these interventions.Methods: Empirical studies applying mindfulness and/or compassion to PWS were included. Database (PubMed, CiNii), registry (CENTRAL, ICTRP, ClinicalTrials.gov), Google scholar, citation, and manual searches were conducted (last searched on November 10, 2021). Adjusted standardized mean differences (SMDs) were presented through forest plots. Risk of bias was assessed through a tool developed by the National Institutes of Health. Results: Eighteen studies (n = 195, excluding controls) were included. Ten studies, all of which showed some risk of bias, allowed calculation of SMDs of pre-post comparison. Some SMDs calculated in certain studies which were potentially less affected by bias appeared consistent with those in previous studies. Mindfulness has been used in several different treatments including speech treatments. A clinical trial of self-compassion is ongoing.Discussion: Mindfulness interventions have been applied to PWS in several treatment approaches and can have beneficial impacts. However, there is a risk of bias, including bias potentially caused by questionable research practices and publication and/or reporting bias.