Polylactides (PLA), produced by abundant renewable naturally occuring resources, is the most promising biodegradable polymer to replace conventional petro-based thermoplastics. However, the low heat resistance restricts its application in various fields. Fortunately, the stereocomplexe crystal (SC) formed in the blends of poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA) with melting temperature 50 ºC higher than that of homochiral crystals (HC) provides a promising solution to high thermal resistant PLA materials. Nevertheless, it is not an easy task to obtain samples with high SC content especially in melting blened molecular weight PLLA/PDLA blends due to the microscopic phase separation into a PDLA-rich and a PLLA-rich phase. In present work, a simple and effcient method, i.e. thermal treatment, was applied to PLLA/PDLA blends. The thermal treatment conditions were carefully determined by using DSC tests. The optimal thermal treatment temperature and duration is 210 ºC and 10 min, respectively. Furthermore, the crystallization process was traced by in-situ WAXD during thermal treatment process under the optimal treatment condition. As a result, samples with exclusive SC and crystallinity of over 50% were obtained and a template effect is proposed to explain this phenomenon, i.e. newly formed SCs are induced by the surface of residual SCs. It is worthy to note that this simple and effcient thermal treatment method is open to almost all samples prepared through commercial processings to achieve high SC content and reasonable heat resistance. Keywords: PLA, stereocomplex crystals, thermal treatment