An internal combustion engine start controller in a vehicle that includes: a power source; an internal combustion engine that is started by using electric power supplied from the power source; a first motor; and a first electric power converter that is constructed so as to be able to perform electric power conversion between the power source and the first motor through switching control of power semiconductor elements is provided. The start controller includes: a start detecting device for detecting whether the engine is in a starting operation; and a first frequency setting device that, when the engine is in a starting operation, sets a switching frequency of the first electric power converter to a frequency lower than that used when the engine is not in a starting operation.