At the Lianglitage Mountrain in the eastern Bachu area, Xinjiang, outcrops the Lianglitage reefs (Yijianfang Formation) of Middle Ordovician and Kaidi reefs (mid Lianglitage Formation) of Upper Ordovican. The former, about a few meters to a few tens meters in thickness, has echinoderm banks reefframe builders, which consists of receptaculitids and formed typical framestone. Primary porosities widely developed at the centre of receptaculitids, with lime mud as matrix. Lamniar or crustiform algae growing around receptaculitids can be defined as crustform algaereceptaculitids community. The reefbuilders in the small mounds of Lianglitage Group comprise mainly branched dasycladales, with some large spherical dasycladales as secondary builders. Primary or secondary porosities were filled with sparry calcite. Small reef units usually less than 1 min diameter consists of abundant dasycladales and minor Epimastopora, forming so called the branched dasycladales community. But the bigger reef (with a diameter ranging from 10 to 30 m) of Upper Lianglitage Group often consists fo branched dasycladales and a unknown small spherical organism (probably dasycladale), constituting a so called spherical algae a kind of branched dasycladale community.