Electric heating catalyst

An electric heating catalyst comprising:

• a heat generation element that is electrically energized to generate heat so that a catalyst is heated by the generation of heat;
• a case that receives said heat generation element therein;
• an insulating support member that is arranged between said heat generation element and said case for supporting said heat generation element and insulating electricity;
• an inner pipe that is a tubular member which is inserted into said insulating support member so as to be located between said heat generation element and said case, wherein said inner pipe has an end thereof protruding into an exhaust gas from an end face of said insulating support member, and said inner pipe has an electrically insulating layer formed on an entire surface thereof, or said inner pipe is formed of an electrically insulating material;
• and
• an inner pipe heater that is supplied with electricity through a path which is different from a path through which electricity is supplied to said heat generation element, thereby to heat a protrusion portion in said inner pipe which protrudes into the exhaust gas from the end face of said insulating support member.