Poly(ε-caprolactone) (PCL) with weight-average molar mass over 10000 g/mol was synthesized by microwave-assisted ring-opening polymerization of ε-caprolactonc (ε-CL) with malcic acid (MA) as initiator (2.45 GHz, 360 W, 85 min). Ibuprofen-PCL controlled release system was prepared directly by the ROP of ε-CL in its mixture with ibuprofen. The release of ibuprofen from the system was sustained and steady.