<p>A multi-nucleic-acid amplification reaction tool of an embodiment includes a support and a plurality of types of primer sets. The support is configured to be able to support a reaction field of a liquid phase. A plurality of types of primer sets are fixed in a releasable state, for each type, on mutually independent fixing regions of at least a surface of the support, which is in contact with the reaction field, when the liquid phase forms the reaction field. A plurality of types of primer sets are configured to amplify the respectively corresponding target sequences.</p>
