The present invention relates to a probe synthesis method and a probe synthesis kit for nucleic acid detection, which are intended for the fluorophore labeling and detection of a target gene. In this method, a probe unit for analyte nucleic acid recognition having a base sequence specific to an analyte nucleic acid and plural labeled probe units each having a fluorophore labeled internal base are hybridized to oligonucleotides complementary thereto, and the adjacent probe units are bonded by ligation. As a result, an analytical probe with increased fluorescence intensity is synthesized easily and inexpensively, while the number of fluorophore labels is controlled.