A detection method of detecting a position of an uppermost substrate of a plurality of substrates stacked on each other includes applying illumination to a region covering a portion of an edge of the uppermost substrate and a portion of a lower substrate stacked with the uppermost substrate, identifying a position of the edge of the uppermost substrate based on a position of a step-like portion present in the region due to a step formed between the uppermost substrate and the lower substrate, and identifying a position of the uppermost substrate based on the position of the edge of the uppermost substrate.