A fluid analysis chip includes a channel formed within the chip. The chip includes a sample inlet and a sample outlet communicating with an outside of the chip, where the sample inlet and the sample outlet communicate with each other through the closed channel. An expanding part of the channel is formed in a longitudinal direction of the channel in such a manner that a pair of inner walls of the channel define an inner surface of the expanding part, and the expanding part has a larger sectional area than the channel.