Amy Mainzer (born January 2, 1974) is an American astronomer, specializing in astrophysical instrumentation and infrared astronomy. She was the deputy project scientist for the Wide-field Infrared Survey Explorer and is the principal investigator for its NEOWISE extension to study minor planets and for the future Near Earth Object Surveyor space telescope mission.

Her research interests include asteroids, brown dwarfs, planetary atmospheres, debris disks, star formation, and the design and construction of new ground- and space-based instrumentation.