Mark Adler (born 1959) is an American software engineer.
He is best known for his work in the field of data compression as the author of the Adler-32 checksum function, and a co-author of the zlib compression library and gzip.
He has contributed to Info-ZIP, and has participated in developing the Portable Network Graphics (PNG) image format.
Adler was also the Spirit Cruise Mission Manager for the Mars Exploration Rover mission.