NGC 6242 is an open cluster of stars in the southern constellation Scorpius. It can be viewed with binoculars or a telescope at about 1.5° to the south-southeast of the double star Mu Scorpii. This cluster was discovered by French astronomer Nicolas-Louis de Lacaille in 1752 from South Africa. It is located at a distance of approximately 4,350 ly (1,335 pc) from the Sun, just to the north of the Sco OB 1 association. The cluster has an estimated age of 77.6 million years.

A microquasar with the designation GRO J1655-40 is located in the vicinity of NGC 6242 and is moving away from the cluster with a runaway space velocity of 112±18 km/s. It may have originated in the cluster during a supernova explosion ~2.2×10 year ago.