The present invention is directed towards a Multiple-Input Multiple-Output (MIMO) omnidirectional antenna. The Multiple-Input Multiple-Output (MIMO) omnidirectional antenna comprising three or more column sets, where the three or more column sets are arranged in a centrosymmetric arrangement about a centre point of the antenna. Each column set comprises two or more antenna columns and each of the antenna columns mounts a plurality of radiators thereon. Each antenna column receives no more than two signals to be transmitted, and, each of the antenna columns is arranged to be axisymmetric about a radially-directed axis created between the centre point of the antenna and a transverse cross-sectional midpoint on the antenna column. Therefore, each radiation pattern established by each of the three or more column sets is centrosymmetric about the centre point of the antenna, and, is axisymmetric about the radially-directed axis.