Several CaCu5-type compounds in which Ce is combined with a 3d element (or Cu) and an s, p element have been studied by time-of-flight neutron diffraction at room temperature. A strong site preference of the s, p elements was observed. It is shown that Al and Ga occupy almost exclusively the 3g site. This behaviour is in contrast to that of B, which is known to substitute almost exclusively into the 3g site in CeCo5.