Natural and acrylonitrile-butadiene rubbers possess different vulcanization characteristics. Selection of the vulcanization system and temperature affects the mechanical properties of vulcanized natural rubber (NR) and acrylonitrile-butadiene rubber (NBR). In the present work, the effect of vulcanization temperature (150, 160, 170 and 180oC) on the mechanical properties of NR and NBR vulcanizates was studied. The effect of different vulcanization system (semi efficient, efficient and sulfur donor) was studied in NR blends, while the effect of different acrylonitrile content (26, 28 and 33 wt %) was studied in NBR blends. The NBR curing characteristics and mechanical properties data showed that vulcanization at low temperature (150oC) was suitable for low acrylonitrile-NBR, whereas that at high temperature (170oC) was suitable for high acrylonitrile-NBR. In addition, the semi efficient system at low temperature vulcanization (150oC) was suitable for natural rubber.