BACKGROUNDS: Mindfulness-based interventions (MBIs) delivered via the Internet become increasingly popular for improving maternal mental health, but the effectiveness of internet-delivered MBIs (iMBIs) is still unclear. METHODS: PubMed, PsycINFO, Embase, Scopus, CINAHL, and Cochrane Central Register of Controlled Trials were searched. We included studies that were randomized controlled trials (RCTs), quasi-experimental study design, and pre-post test design and contained information on the population of interest (women during pregnancy or within one year after delivery), intervention contents (mindfulness components), and intervention delivery formats (internet-based). ROBINS-I and RoB 2 were used to rate the risk of bias in non-RCTs and RCTs, respectively. RESULTS: Eleven studies composed of six RCTs and five non-RCTs were included. The overall risk of bias was high. IMBIs are effective in improving maternal depression and mindfulness and self-compassion. However, limited by the small number of studies included in the review, effect sizes of iMBIs cannot be estimated. Characteristics of iMBIs (delivery formats, duration, et al.) and studies (study design, measures et al.) were described. CONCLUSION: iMBIs are still in the initial stage. Studies with rigorous study design and larger sample size, and determining the optimal delivery formats and duration and intensity of interventions are necessary.