An exhaust gas purifying device for an internal combustion engine, comprising: an electrically heated catalyst which is provided on an exhaust passage of the internal combustion engine, which purifies the exhaust gas drawn to the exhaust passage, and which is warmed by electrification; the device comprising: an electrification characteristic setting unit which is configured to set an electrification characteristic which is a curve where the electrification resistance value of the electrically heated catalyst is given in relation to any one of the temperature of the electrically heated catalyst, supplied energy to the electrically heated catalyst and an electrification time to the electrically heatedcatalyst, in accordance with the supplied power to the electrically heated catalyst at a time of starting the electrification of the electrically heated catalyst, a unit which is configured to perform an abnormality determination and an electrification control for the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, a permissible resistance range setting unit which is configured to set a permissible resistance range for determining an actual electrification characteristic of the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, and an abnormal electrification determining unit which is configured to obtain the actual electrification characteristic of the electrically heated catalyst, and to determine the abnormal electrification of the electrically heated catalyst when the actual electrification characteristic becomes out of the permissible resistance range, wherein the permissible resistance range setting unit is configured to set the permissible resistance range in accordance with the supplied power to the electrically heated catalyst at the time of starting the electrification. an electrically heated catalyst which is provided on an exhaust passage of the internal combustion engine, which purifies the exhaust gas drawn to the exhaust passage, and which is warmed by electrification; the device comprising: an electrification characteristic setting unit which is configured to set an electrification characteristic which is a curve where the electrification resistance value of the electrically heated catalyst is given in relation to any one of the temperature of the electrically heated catalyst, supplied energy to the electrically heated catalyst and an electrification time to the electrically heatedcatalyst, in accordance with the supplied power to the electrically heated catalyst at a time of starting the electrification of the electrically heated catalyst, a unit which is configured to perform an abnormality determination and an electrification control for the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, a permissible resistance range setting unit which is configured to set a permissible resistance range for determining an actual electrification characteristic of the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, and an abnormal electrification determining unit which is configured to obtain the actual electrification characteristic of the electrically heated catalyst, and to determine the abnormal electrification of the electrically heated catalyst when the actual electrification characteristic becomes out of the permissible resistance range, wherein the permissible resistance range setting unit is configured to set the permissible resistance range in accordance with the supplied power to the electrically heated catalyst at the time of starting the electrification. an electrification characteristic setting unit which is configured to set an electrification characteristic which is a curve where the electrification resistance value of the electrically heated catalyst is given in relation to any one of the temperature of the electrically heated catalyst, supplied energy to the electrically heated catalyst and an electrification time to the electrically heatedcatalyst, in accordance with the supplied power to the electrically heated catalyst at a time of starting the electrification of the electrically heated catalyst, a unit which is configured to perform an abnormality determination and an electrification control for the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, a permissible resistance range setting unit which is configured to set a permissible resistance range for determining an actual electrification characteristic of the electrically heated catalyst, based on the electrification characteristic set by the electrification characteristic setting unit, and an abnormal electrification determining unit which is configured to obtain the actual electrification characteristic of the electrically heated catalyst, and to determine the abnormal electrification of the electrically heated catalyst when the actual electrification characteristic becomes out of the permissible resistance range, wherein the permissible resistance range setting unit is configured to set the permissible resistance range in accordance with the supplied power to the electrically heated catalyst at the time of starting the electrification.