Cancer is a major cause of morbidity and mortality worldwide and therefore there has been interest in discovering the phytoconstituents of medicinal plants exhibiting anticancer activities. Morinda citrifolia L., commonly known as Noni, has shown anticancer properties in in vitro, in vivo, and in clinical studies. A systematic review was conducted to collate scientific evidence on the anticancer properties of M. citrifolia using pre-determined keywords on 5 electronic databases: MEDLINE, CENTRAL, LILACS, Web of Science, and EBSCOHost. A total of 51 clinical and preclinical studies comprising 41 efficacy and 10 safety studies were included in this review. Our findings showed that M. citrifolia demonstrated various anticancer properties in different cancer models, via multiple mechanisms including antitumor, antiproliferative, pro-apoptotic, antiangiogenesis, antimigratory, anti-inflammatory, and immunomodulatory activities. M. citrifolia is deemed to be a potentially valuable medicinal plant in the treatment of cancer through its many intrinsic pathways. More well-designed and reported preclinical efficacy and safety studies are needed to allow for better translation into future clinical studies which could further substantiate the role of M. citriflolia in cancer treatment.