Sh 2-306 (also designated RCW 10), is an emission nebula and H II region located in the southern constellation Puppis. It is catalogued in the Sharpless catalog and forms part of a large star-forming complex within the Perseus Arm of the Milky Way. It is located close to Sh 2-309.

Three stars are responsible for the ionization of the nebula LSS 458 (O6.5V((f))z), LSS 499 (OB) and LSS 467 (O9). These stars are embedded within a giant molecular cloud complex sometimes referred to as JKK96 D. Sh 2-306 is situated near the center of the GS234-02 supershell, a vast infrared-emitting ring structure spanning several degrees, believed to be the result of multiple supernova explosions and stellar winds from previous generations of massive stars.