Novel 5-Z-amino-d-valerolactone (5-NHZ-VL) was synthesized with aim to prepare degradable polyesters and copolyesters having amino pendant groups. Following a straightforward and efficient synthetic pathway, 5-NHZ-VL was obtained in only two steps and up to 50 % yield. The monomer was fully characterized by 1H NMR, 13C NMR, ESI mass spectrometry and HPLC. Various conventional conditions were tested for this lactone ring opening polymerization and led to the novel corresponding poly(5-NHZ-VL) (Mn = 7000 g/mol ; PD = 1.2). Following this homopolymerization, 5-NHZ-VL was copolymerized with e-caprolactone to generate a family of copolyesters with an amino-group content ranging from 10 to 80 %. Finally, the polyelectrolyte poly(5-NH3+-VL) was recovered by removal of the protecting group under acidic conditions and integrity of the polyester backbone was confirmed by 1H NMR.