In vitro studies show that tea tree oil is capable of killing methicillin-resistant Staphylococcus aureus (MRSA) in a laboratory setting. This review of randomized controlled trials (RCTs) was undertaken to find out whether it is effective at eradicating MRSA colonization compared to standard mupirocin-based regimens in colonized patients. A wide range of databases and internet sources were searched to identify published and unpublished studies. Two RCTs were found that researched the effectiveness of tea tree oil preparations against MRSA. One small RCT (n = 30) showed a large but non-significant improvement at eradicating MRSA compared to traditional treatment, whereas a larger study (n = 224) demonstrated little difference in rates of eradication overall (41% for tea tree and 49% for mupirocin, p = 0.286). However, the larger study found that those with nasal colonization receiving a tea tree regimen were more likely to remain colonized with MRSA in the nose (absolute risk increase 31%, p<0.001). Currently there is insufficient evidence to support the routine use of tea tree oil in clinical practice for eradication of MRSA colonization.