The present disclosure relates to a reagent storage device and a bio-reaction apparatus including the same. Provided is a reagent storage device connected to a biochip to provide reagents into the biochip. The reagent storage device includes a storage container having a tube shape of which one end is opened, and the other end opposite to the one end is closed and a plurality of diaphragms provided in the storage container and installed to be closely attached to an inner wall of the storage container. Here, the diaphragms are spaced apart from each other in one direction in which the one end and the other end are disposed opposite to each other, and each of the diaphragms includes a through-hole passing therethrough.