A micro fluid chip includes a first chip and a second chip. The first chip includes a first substrate having a fluid channel and a partition wall, and a first film made of resin. The second chip includes a second substrate having a recess, and a second film made of elastomer. The second film has an elastic modulus higher than that of the first film. The first chip and the second chip are stacked in such a manner that the partition wall and the recess face each other with the first film and the second film therebetween. By setting the inner side of the recess to a negative pressure, a gap is formed between the first film and the partition wall, and thus a fluid channel is opened.