Abstract: A device for automatically cultivating cells in parallel in cell culture vessels, in particular microtiter (MT) plates (2), having a housing (23) in which are disposed an observation unit (3) comprising at least one microscope (7) and at least one camera (6), a receptacle device (4) for receiving the cell culture vessels, and a fluid distribution unit (5) for automatically filling and/or emptying the cell culture vessels, in particular the wells (17) of microtiter (MT) plates (2), with fluid, wherein the climatic conditions in the device, in particular the gas composition and temperature, can be controlled in a closed loop at least in the region of the cell culture vessels, wherein a climate chamber (21) is provided in the housing, in which a desired temperature and/or a particular gas composition can be adjusted automatically, and in which the receptacle device (4); having the cell culture vessels (2) is at least partially integrated.