From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new dihydrofurocoumarin, named pandanusin A (1) and 15 known compounds, including one furanocoumarin (2), two coumarins (3, 4), four lignans (5-8), one neolignan (9), two flavonoids (10, 11), three phenolics (12-14), one monoglyceride (15) and one monosaccharide (16) were isolated by various chromatography methods. Among them, compounds (3-5) were obtained from the Pandanus genus for the first time and compounds (9-14, 16) were reported from this species for the first time. Their structures were elucidated by HR-ESI-MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolated compounds (1-12, 14) showed better α-glucosidase inhibitory activity (IC50 = 42.2, 36.5, 84.7, 73.2, 40.8, 26.7, 76.5, 33.8, 68.1, 14.4, 22.1, 81.5, 43.8 μM, respectively) than the standard drug acarbose (IC50 = 214.5 μM).