Abstract: Provided are an aliphatic polyester resin foam which has a compressive stress equal to or below that of 50-fold expanded polystyrol foam and which exhibits excellent degradability and excellent shock absorption performance, a biodegradable flower arrangement holder which has not only such low compression strength as to permit arbitrary insertion of flowers but also supporting power and which is excellent in water permeability and water-holding capacity, and processes for production of both. Aliphatic polyester resin expansion moldings which are produced from expanded aliphatic polyester resin particles and which have weight-average molecular weights of 5000 to 140000 and expansion ratios of 10 or above.