This paper prepared novel biodegradable and pH-sensitive microgels based on Poly(epsilon-caprolactone)-Pluronic-Poly(epsilon-caprolactone)-dimethacrylate (PCFC-DMA), Poly(ethylene glycol) dimethacrylate (PEG-DMA) and methylacrylic acid (MAA) cross-linked with N,N'-methylenebisacrylamide (BIS), initiated by NaHSO(3), K(2)S(2)O(8). The blank microgels were prepared by inversed-phase suspension polymerization method and pH sensitivity of microgels was characterized. Then the blank microgels were loaded with hydrophilic model drug vitamin-12 (VB-12) and in vitro drug release behaviour was also studied here.