Siêu đám thiên hà hay siêu thiên hà, cụm thiên hà, hay siêu quần thiên hà (Tiếng Anh là Superclusters) là hệ thống gồm các thiên hà, quần tụ thiên hà, có các dây, các mạng, liên kết với nhau thành một hệ thống. Với kích thước khổng lồ của siêu đám, các thành viên trong đó không phải liên kết ràng buộc với nhau bằng lực hấp dẫn.
It contains the Local Group with our galaxy, the Milky Way. It also contains the Virgo Cluster near its center, and is sometimes called the Local Supercluster. It is thought to contain over 47,000 galaxies.
In 2014, the newly announced Laniakea Supercluster subsumed the Virgo Supercluster, which became a component of the new supercluster.
Discovered in 1999 (as ClG J0848+4453, a name now used to describe the western cluster, with ClG J0849+4452 being the eastern one), it contains at least two clusters RXJ 0848.9+4452 (z=1.26) and RXJ 0848.6+4453 (z=1.27) . At the time of discovery, it became the most distant known supercluster. Additionally, seven smaller groups of galaxies are associated with the supercluster.
A rich supercluster with several galaxy clusters was discovered around an unusual concentration of 23 QSOs at z=1.1 in 2001. The size of the complex of clusters may indicate a wall of galaxies exists there, instead of a single supercluster. The size discovered approaches the size of the CfA2 Great Wall filament. At the time of the discovery, it was the largest and most distant supercluster beyond z=0.5 
This supercluster at the time of its discovery was the largest supercluster found so deep into space, in 2000. It consisted of two known rich clusters and one newly discovered cluster as a result of the study that discovered it. The then known clusters were Cl 1604+4304 (z=0.897) and Cl 1604+4321 (z=0.924), which then known to have 21 and 42 known galaxies respectively. The then newly discovered cluster was located at 16h 04m 25.7s, +43° 14′ 44.7″
^Tanaka, I. (2004). “Subaru Observation of a Supercluster of Galaxies and QSOS at Z = 1.1”. Studies of Galaxies in the Young Universe with New Generation Telescope, Proceedings of Japan-German Seminar, held in Sendai, Japan, July 24–28, 2001. tr. 61–64. Bibcode:2004sgyu.conf...61T.