Morinda citrifolia L. (Rubiaceae), commonly known as noni, is a small evergreen tree traditionally used across the Indian coastline and the wider Indo-Pacific region for a broad range of ailments. The present study evaluated the preliminary phytochemical profile, in vitro antioxidant activity, and in vitro anti-haemolytic activity of the ethanolic extract of the leaves and fruits of M. Citrifolia, following authentication of the plant material by the Department of Botany, The American College, Madurai. The extract was obtained by Soxhlet extraction and screened qualitatively for major phytochemical classes. Antioxidant activity was assessed by the potassium ferricyanide reducing-power method, and protection of human erythrocytes against hydrogen-peroxide-induced haemolysis was assessed using quercetin as the reference standard. Preliminary screening indicated the presence of steroids, cardiac glycosides, phenolics, terpenoids, resins, carbohydrates, flavonoids, reducing sugars and saponins, with alkaloids and anthraquinones absent. The ethanolic extract exhibited concentration-dependent reducing power, although lower than that of ascorbic acid, and showed a concentration-dependent reduction in hydrogen-peroxide-induced haemolysis of erythrocytes, comparable in trend to quercetin. These findings support the traditional use of M. citrifolia as a source of natural antioxidant and membrane-protective constituents, and provide a basis for further isolation and in vivo evaluation of its bioactive phytoconstituents.