An imaging system comprises: a light source unit; an image sensor unit which is provided with a light receiving unit that performs a rolling shutter imaging operation; a trigger signal output unit which outputs a trigger signal that indicates either a timing at which reading of a first line within a same frame starts in the light receiving unit or a timing at which reading of a last line within a same frame has ended in the light receiving unit; an image adding unit which adds N frames of an image and outputs the same on the basis of the trigger signal; and a light source control unit which causes the light source unit to start emitting light after a predetermined amount of delay time has passed from an input of the trigger signal, and causes the light source unit to stop emitting light after reading of the frame N-1 in the first line is completed in the light receiving unit and before reading of the frame N begins.