An exposure control device for flash photography having a first program mode wherein an exposure time is fixed at the flash synchronizable shutter speed and a diaphragm aperture value is changed at a high brightness region according to the brightness of an object to be photographed, and a second program mode or flash photography wherein the diaphragm aperture value and the exposure time within a flash synchronizable shutter speed are changed within a wide range of the brightness of the object to be photographed, and a combination of the diaphragm aperture value and the exposure time gives an exposure predetermined by taking the flash light emission into consideration. The exposure control unit is capable of carrying out the exposure control in the first or second program mode selected by a manually operated mode selecting unit.