Type 2 diabetes mellitus (T2DM) is a major health risk and dominant cause of global mortality and morbidity. Disease-specific support from peers with similar chronic condition has shown to improve chronic disease self-management outcomes. The purpose of this systematic review is to summarise the existing evidence on the impact of peer coach-led type 2 diabetes mellitus self-management interventions on glycaemic control and self-management outcomes. Databases including MEDLINE, PubMed, CINAHL Plus, Scopus, ProQuest Central, ScienceDirect, web of science, Wiley Online Library and UOW Library were searched for eligible papers. Thirteen randomised controlled trials (RCTs) published between 2008 and 2021 were included in this review. Random-effects meta-analyses found that there were statistically significant changes in Haemoglobin A1c HbA1c) after the interventions. However, the meta-analyses showed no significant changes in LDL (low-density lipoprotein), BMI (Body mass index), systolic BP