Masten Space Systems is an US rocket company that is currently developing a line of reusable spacecraft, and related rocket propulsion hardware.
Masten Space Systems designs, builds, tests and operates reusable launch vehicles.
Masten Space Systems competed in the NASA and Northrop Grumman Lunar Lander Challenge X Prize in 2009, winning the level one second prize and the level two first prize. On November 2, 2009 it was announced that Masten Space Systems had won first place in the level two category, with Armadillo Aerospace coming in second.