Cell culture device having culture medium replacement function

A cell culture apparatus having a culture medium replacement function, wherein

• at least one set of upper and lower discs each fixed to a rotatable shaft is horizontally arranged inside an incubator chamber, Petri dishes in each of which cells and a culture medium are put are held on the lower disc, top lids are held on the upper disc, a lower side of each of the top lids is open, it is possible to achieve a state in which the lower disc and the upper disc are brought vertically close to each other to cover the Petri dishes with the top lids and a state in which the lower disc and the upper disc are vertically separated from each other and one of the lower disc and the upper disc is rotated by a predetermined angle to laterally shift the top lids from the Petri dishes so that the Petri dishes are partially exposed, culture medium replacement means is inserted into the exposed portion of a Petri dish from the upper side through a first insertion hole of a plurality of insertion holes formed on the upper disc, and the culture medium is replaced, the culture medium replacement means is then retracted, and the lower disc and the upper disc are rotated and vertically displaced to cover the Petri dishes with the top lids to continue cell culture, wherein the plurality of insertion holes are formed to penetrate the upper disc, each of the plurality of holes being located at a position near to a corresponding one of the top lids.