The aqueous ethanolic extract of the aerial parts of Calothamnus quadrifidus, R. Br (Myrtaceae) showed significant biological activities including analgesic, anti-inflammatory, hypoglycaemic and antioxidant activities. Fifteen compounds were isolated and characterized from the same extract after chromatographic column fractionation. Compounds (1-3) are phenolic acids. The remaining compounds (4-15) belong to the group of plant natural products flavonoid. This is the second report regarding the natural occurrence of compound (8), quercetin 3-O-β-4C1-D-glucuronide-3′- sulphate.