The crystallization behavior of the poly(ethylene oxide) (PEO) component in poly(butylene succinate) (PBS)/PEO blends with the middle PEO content was investigated as a function of isothermal crystallization temperature of the PBS component (T-IC,T-PBS) using differential scanning calorimetry (DSC). It is found that the crystallization behavior of the PEO component in these blends is significantly affected by Tic,PBS. Small-angle X-ray diffraction (SAXS) measurements were performed to explore the origin of the T-IC,T-PBS dependence of crystallization of PEO component. On the basis of the SAXS measurements and the results of our previous work [Macromolecules 2004, 37, 3337-3345], it is suggested that Tic,PBS controls the location distribution of the PEO component in the blends after the crystallization of the PBS component and thus significantly affects the crystallization behavior of PEO.