This study focused on low molecular weight poly-L-lactic acid (PLLA) and amorphous poly lactic acid (PDLLA) thin films of blends of crystalline material type. After the isothermal crystallization process, low molecular weight poly(l-lactic acid) film will form the pattern which is different from the traditional spherulite. With the crystallization temperature changes, the crystallization patterns of polymer film will change accordingly. Observed using optical microscope (OM) crystal morphology changes, and the use atomic force microscope (AFM) to observe the crystal growth of lamellae patterns, and finally we found that the preferences of the lamellae growth pattern affect the morphology. In addition, we blended with different ratios of non-crystalline polymer PDLLA, by changing the glass transition temperature, the equilibrium melting point and crystalline phase volume fraction, observed how crystalline morphology change by thermodynamic parameters.