Abstract: The present invention relates to a multi-hybridization set for DNA microarray assay, which comprises: a lower plate in which a DNA microarray is mounted; an upper plate which is coupled to the lower plate, and in which one or more O-rings are attached to the lower surface of the upper plate coming in contact with the DNA microarray such that separate spaces are formed when the upper and lower plates are coupled to each other, the upper plate having sample injection holes formed inside of the O-ring; and means for coupling the upper and lower plates to each other. The multi-hybridization set of the present invention allows the DNA microarray assay of several samples to be performed at once. In addition, according to this multi-hybridization set, the problem of contamination caused by oil and dust, which occurs due to the use of the existing cover glass, can be solved.