To provide an etching completion detecting method capable of correctly and reliably detecting etching completion even when manufacturing a very small structure by performing the etching on a work, a structure for detecting etching completion, and an etching method.

When a structure for detecting etching completion performs the etching of a layer 103' to be etched via a mask 11' under the same or equivalent condition to that of the etching on a work, and a portion of the layer 103' to be etched corresponding to an opening part 113 is removed before reaching an etching stopping member 102'. Since the side etching is generated along the etching stopping member 102', the portion of the layer 103' to be etched corresponding to a portion 114 for detection is detached from the etching stopping member 102', and etching completion is detected thereby.