Effects of the mixing ratio of poly(DL-lactide) (PDLLA) and poly(epsilon-caprolactone) (PCL) on the thermal and mechanical properties and morphologies of the solution-cast blends were investigated by differential scanning calorimetry (DSC), polarizing microscopy, tensile tests, and dynamic mechanical analysis. The presence of amorphous PDLLA did not disturb crystallization of PCL over the PDLLA content [X(PDLLA) = PDLLA/(PCL + PDLLA)] from 0.1 to 0.9 and allowed PCL to form spherulites over X(PDLLA) ranging from 0.1 to 0.6. The spherulite radius was larger for the blends than for the nonblended PCL. Phase separation occurred for the blends with X(PDLLA) between 0.1 and 0.9. T-m of PCL remained unchanged in the X(PDLLA) range up to 0.6 but decreased at X(PDLLA) above 0.6, whereas the crystallinity of PCL was constant around 60%, irrespective of X(PDLLA). The tensile strength (sigma(B)), the yield stress (sigma Y), the Young’s modulus (E), and the storage modulus (G’) of the blends increased monotonously with X(PDLLA) if sigma(B) at X(PDLLA) = 0 and 0.6 and sigma(Y) at X(PDLLA) = 0.6 were excluded. Elongation-at-break (epsilon(B)) of PDLLA increased dramatically, while epsilon(B) of PCL decreased remarkably when a small amount of the other component was added. Equations and parameters predicting sigma(Y), E, and G’ of the PCL-PDLLA blends were proposed as a function of X(PDLLA).