To simply detect the existence of a target nucleic acid sequence in a specimen by transferring the specimen comprising a tissue, a cell, a subcellular biological structure, etc., to a thin film support, folding it thereon, and subsequently subjecting the formed sample to a hybridization method, etc.

This method for detecting the presence of a target sequence in a single-strand or double-strand nucleic acid in a specimen comprising a tissue, a cell, a subcellular biological structure, etc., comprises transferring and holding the specimen to a thin film support (e.g. a nitrocellulose film), holding it thereon, and subsequently subjecting the formed sample to a nucleic acid-proliferating method such as a southern and a northern hybridization methods or a polymerase chain reaction(PCR) method. Thus, the peeling of a sample slice, etc., on the preparation of a sample and on the detective operation of a gene can be prevented, and the existence of a target nucleic acid sequence in the sample can simply be detected.