When there is a crack on the straight edge of a plate under tension, to prevent further development of the crack, a circular hole is drilled at the end of the crack. Considering the above case, the author has solved the problem of a semi-infinite plate with a circular hole connected to the straight edge by a straight and narrow slit subjected to uniform tension parallel to the straight edge. He has obtained stress distributions on the plate and the factors of stress concentration at the bottom of the circular hole.