Nowadays, Emissions of pollutants into atmosphere from motorcycle in the cold-start condition are becoming more in urban societies. One of the applicable methods to reduce emissions is using the electrically heated catalyst (EHC). In this study simulation the effects of using EHC on CO emission for various heating temperatures (600 K, 800 K and 1000 K) was investigated in the inlet of catalytic converter in the cold-start condition of a motorcycle engine. Firstly, the geometry of the model was drawn in Gambit and then CFD code FLUENT was used for prediction of catalytic converter light-off temperature and CO conversion. The results showed that by heating the catalyst, the conversion efficiency could be improved. It was revealed that a high temperature rising rate induced a high CO conversion efficiency and also the larger area of catalytic converter can be reached to its activation temperature. Beside the heating temperature 1000 K has better condition than that of other heating temperatures.