NGC 6553 is a globular cluster in the constellation Sagittarius.

[2] Its Shapley–Sawyer Concentration Class is XI,[2] meaning the star concentration is very loose even at the center; it has stars of magnitude 20 and dimmer.

It is located just over a degree southeast of Messier 8, the Lagoon Nebula.

Unlike common globular clusters, NGC 6553 is relatively metal-rich, and there is evidence of at least two periods of star formation.

[4] Due to a complex star-forming record, the stars in the cluster are differing in composition, most notably in concentrations of sodium and aluminium.