The main aim of this project is to prepare ABS/PC heat resistance blend. For this purpose appropriate additive and compatibilizers was used. The blend was prepared in an co-rotate twin extruder. ABS-g-MA, SAN-g-MA, PE-g-MA compatibilizers were used in 3, 5 and 10 Phr. Evaluation of physical, mechanical and thermal properties of blends such as tensile and flexural strength, impact strength, hardness and specialy heat distortion temperature showed that the addition of ABS-g-MA ,SAN-g-MA and PE-g-MA compatibilizer enhanced this properties, so that Using the 5% ABS-g-MA compatibilizer in ABS /PC blend improved tensile strength 60%, flexural modul 44%, hardness 26% and HDT 33 0 c. Addition of 5% ABS-g-MA compatibilizer, thermal destruction temperature in ABS/PC blend increased about 50 0 c. Also, morphological properties of the blends have been studied by SEM. SEM images of compatibilized blends show that with addition of compatibilizer, ABS particle size distributed in PC matrix have reduced and particle distribution is smoother. SEM images of ABS/PC/ABS-g-MA show smaller particle size and better distributtion. Generally, addition of mineral nano particles to the polymer matrix can increase thermal stability. In this project nano-silica particles (SiO 2 ) is used to increase the thermal stability. SEM images show that with addition 1% nano-silica distibuted particle size is about 50 nm but with increasing in nano-silica content particles in ABS/PC blend was aggregated. With using nano-silica particle tensile strength 6%, flexural strength 4%, flexural modul 9% and HDT 2 0 c will be improved. Initiate and terminate temperature of thermal destruction did not change much.With Addition of nano-silica, elongation at break(%) reduce. The reason of this is due to the reduction in chain mobility. Furthermore, compatibilizer causes reduction in particles aggregation and therefore the interface area in the certain concentration of silica increased.