The properties of semi-crystalline polymers strictly depends on the morphology of their crystals. The crystal morphology depends on many parameters, one of the most important one is thermal condition and history of the material. In the present research, attempts were made to study the effect of thermal conditions on the final crystal morphology of a semi-crystalline polymer. For this purpose, a phase field model proposed by Kobayashi, were employed to simulate the crystal growth and predict the final morphology. A 2D model with certain thickness was taken into with different thermal condition and fixed nucleating sites. The orientation of each spherulite initiated by a single seed was considered to be different so these crystalline phases could not merge together. The simulation were conducted until steady stare was reached and no further crystalline regions were generated. Results depicted that the spherulite growth showed an s-type trend which was observed in experimental studies. Since spherulites growth took place though lamellar formation and thickening, the crystallinity of 100% would not be possible except for single crystals with perfect structure. The model predicted that through spherulite growth, one may reach to the maximum crystallinity of almost 67%. The denderic growth of spherulite from the initial seed would cause some amorphous regions to be trapped between lamellar regions causing the final crystallinity percent not able to reach 100%. Furthermore, the effect of temperature on the spherulite growth was studied. It was observed that decreasing the supercoiling would result in more homogeneous structure.