Angiopterlactones A (1) and B (2), two unique lactones, and three known lactones, osmundalactone (3), osmundalin (4), and 3,5-dihydroxy-gamma-caprolactone (5), have been isolated from the rhizome of Angiopteris caudatiformis. The structures of I and 2 were determined by NMR and MS methods, and the structure of 2 was confirmed by X-ray crystallography. The absolute configurations of I and 2 were assigned by application of the CD excitation chirality method and the modified Mosher's method. Compound 1 was slightly cytotoxic against HeLa cells, with an IC50 value of 68.8 mu M, and compounds 3 and 4 showed moderate insect antifeeding activity against Plutella xylostella and Heliothis virescens.