Abstract: A kind of blended powder of PA12 and organic rectorite (OREC) was molded by selective laser sintering (SLS) . The st ructure of sintered PA12/ rectorite composite was characterized by XRD , DSC and SEM , and it sthermal stability and mechanical properties were studied. The result s show that the organic rectorite is intercalatedby PA12 during the sintering process , and the thermal stability and the mechanical properties of the PA12/ rectoritenanocomposite are better than those of sintered pure PA12. With 10 % mass f raction of OREC , the tensile st rength ,flexural st rength and impact st rength are improved by 10.7 % , 15.9 % and 38.7 % , respectively , and the thermaldecomposition temperature increases by 27 ℃.