Engine control apparatus

In an air-cooled engine, the temperature of the engine is detected with high accuracy to control fuel injection in optimal conditions. In order to detect the temperature of the engine, a first temperature sensor (21) and second temperature sensor (22) are provided at two spaced portions respectively on a cylinder block (11), and based on the function of a temperature difference between temperatures T 1 and T 2 respectively detected by the first temperature sensor (21) and second temperature sensor (22) and the thermal resistance specific to the engine, a calculating circuit (34) calculates the engine temperature T 0 inside the engine. In this way, the detection (estimation) accuracy of the engine temperature is improved and the optimal engine control is performed.