A cell culture device comprises a fluid mechanism for branching a liquid appropriately in its flow passage when the liquid is injected to a plurality of culture vessels in a set and feeding equal amounts of the culture broth to the culture vessels at the same time. The device, in one form, has one or plural recess portions so that one or plural culture vessels can be contained in alignment, in view of space efficiency, m x n (row x column) pieces of culture vessels can be set in a matrix type. By using a pump, the culture broth is branched by a multi-way valve for distributing the liquid in an appropriate amount from a tank containing the culture broth, and the liquid is fed at the same time to the plurality of culture vessels in the culture vessel set.