Dragon fruit (Hylocereus spp.), renowned for its aesthetic appeal and rich antioxidant content, has gained global popularity due to its numerous health benefits. In Australia, despite growing commercial interest in cultivating dragon fruit, there is uncertainty for local growers stemming from competition with imported varieties. Notably, there is a lack of comparative research on the shelf-life, antioxidant activity, and phytochemical contents of Australian-grown versus imported dragon fruit, which is crucial for enhancing market competitiveness and consumer perception. This study compares the shelf-life, antioxidant activity, and phytochemical content of Australian-grown and imported dragon fruits under ambient conditions, addressing the competitive challenges faced by local growers. Freshly harvested white-flesh (Hylocereus undatus) and red-flesh (H. polyrhizus) dragon fruit were sourced from Queensland and the Northern Territory and imported fruit were sourced from an importer in Queensland. All fruit were assessed for key quality parameters including peel color, firmness, weight loss, total soluble solids (TSS), pH, titratable acidity (TA), total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), total betalain content (TBC), and total anthocyanin content (TAC). The results indicate that Australian-grown white dragon fruits exhibited average one day longer shelf-life with less color degradation, better firmness retention, and less decline in weight loss, TSS, and acidity compared to imported fruits. Australian-grown red dragon fruits showed similar shelf-life compared to fruits from overseas. Antioxidant activities and phytochemicals were consistently higher in Australian-grown fruits throughout their shelf-life. These findings indicate that Australian-grown dragon fruits offer better physical quality and retain more nutritional value, which could enhance their marketability.