Seamus Harper is a fictional character in the television series Gene Roddenberry's Andromeda. He is played by Canadian actor Gordon Michael Woolvett.

Harper is a member of the Andromeda Ascendant crew and is the engineer and fix-it man. Harper is the only member of the Andromeda's crew born and raised on post-Commonwealth Earth. After the Fall, it was conquered by a Nietzschean pride called the Drago-Kazov, who treated unengineered humans poorly, and its inhabitants were frequently attacked by the Magog. The human denizens of Earth lived poverty and conflict, which prompted Harper to run away.

Harper joined the Andromeda crew in 303 AFC (After the Fall of the Commonwealth) along with Beka Valentine, Trance Gemini, and Rev Bem. He was previously recruited onto the Eureka Maru by Captain Valentine's old boyfriend, Bobby Jensen.

Harper's tumultuous upbringing has left him with somewhat deficient social skills, and he prefers to spend his time in the company of machines, constantly fixing and upgrading Andromeda and her various systems. He is quirky, funny, a bit ego-centric, but undoubtedly a genius. He also constructed the humanoid avatar for the Andromeda, called Rommie by the crew. Harper has a neural interface at the base of his skull, which he uses to jack into computers, sentient ships, and programs.

Harper's middle name, "Zelazny," was probably given to the character by the writers as a tribute to the late, beloved science-fiction and fantasy author, Roger Zelazny.