A syringe device includes an administration holder, and a cylinder portion which allows insertion of the administration holder. The cylinder portion includes a coupling holder, a slit holder coupled to the coupling holder, and a double-ended needle assembly disposed slidably in an interior of the coupling holder. A cartridge for a freeze-dry product is mounted, in the administration holder, and a cartridge for solvent is mounted in the coupling holder. When the administration holder is pushed, the double-ended needle assembly slides. When one of the needle points pricks the cartridge for freeze-dry product, the other needle point of the double-ended needle assembly pricks the cartridge for the solvent, and then the needle points unseal the cartridges by a further sliding movement of the double-ended needle assembly.