A self-propelled electric vacuum cleaner includes: a vacuum cleaner main body; a running section for causing the vacuum cleaner main body to run on a floor; a suction section for suctioning dust; a side brush for sweeping the dust on the floor, to the suction section; a floor detection sensor for detecting whether or not there is the floor; and a control section for controlling and driving the running section, the suction section and the side brush in response to an output of the floor detection sensor, in which the side brush includes a rotating shaft coaxially having a through-hole, and a plurality of brush bundles radially spread from one end of the rotating shaft, wherein the floor detection sensor includes an optical sensor provided adjacent to the other end of the rotating shaft to detect whether or not there is an object, through the through-hole.