An engine start control apparatus includes an intake air amount control device for controlling an amount of air supplied to a combustion chamber, a fuel supply device for injecting fuel to be fed into the combustion chamber, and an igniting device for igniting the fuel. The engine start control apparatus further includes an engine operation state detecting unit for detecting an operation state of the engine, an ignition timing retard angle processing unit configured to retard an ignition timing from a start ignition timing to an ignition timing for catalyst warming-up acceleration in response to detection that the engine operation state has shifted to an idling operation state, an intake control device operation unit for operating an intake control device so as to supply such an amount of intake air as to keep the idling operation state when the engine operation state has shifted to the idling operation state, and an injection fuel amount increasing unit for increasing an amount of fuel injected into a cylinder to be shifted to a combustion stroke so as to be combusted in the combustion stroke when the engine operation state has shifted to the idling operation state.