Gas convertor and gas analyzing device

The utility model aims to provide a gas convertor capable of lengthening a configuration area of a catalyst on the basis of a more compact structure, and a gas analyzing device. A plurality of heat transfer roll balls (43) are arranged in the upstream side of a reduction catalyst (41) in a reaction tube (42); after sample gas guided into the reaction tube (42) is heated by contacting with the plurality of heat transfer roll balls (43), the heated gas passes through the reduction catalyst (41) and is reduced by the reduction catalyst (41). Thus, the sample gas can be preheated in a short preheating space by heating the sample gas through the plurality of heat transfer roll balls (43). Therefore, the catalyst configuration area (46) can be lengthened on the basis of a more compact structure even the length of the reaction tube (42) is not lengthened.