Microporous foams of polymer blends of two biodegradable polyesters, poly(L-lactic acid) (PLLA) and poly(E-caprolactone) (PCL), were prepared via thermally induced phase separation method. The phase behaviors of the solutions of the polymer blends in 1,4-dioxane containing water were similar, which would be due to the similar Solubility parameters of the two polymers (20.5-21.1 and 21.2 MPa0.5),). However, the porous structure of the polymer blends dependent oil the blend ratio under the same conditions other than the ratio. Hepatic cells (HepG2 cells) were Cultured on the porous polymer blends. The cells invaded into the scaffold of PCL and PLLA-PCL-blend (1:4) by 1.0 and 1.5 mm, respectively, while they grew near the Surface of the PLLA foams. Blending of biodegradable polyesters has the potential of controlling the porous structure of biodegradable foams.