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Pierson's Puppeteers, often known just as Puppeteers, are a fictional alien race from American author Larry Niven's Known Space books.

Pierson's Puppeteers are described by Niven as having two forelegs and a single hindleg ending in hoofed feet, and two snake-like heads instead of a humanoid upper body. The heads are very small, containing a forked tongue, extensive rubbery lips, rimmed with finger-like knobs, and a single eye per head. The Puppeteer brain is housed not in the heads, but in the "thoracic" cavity well protected beneath the mane-covered hump from which the heads emerge. They use the "mouths" to manipulate objects, as a humanoid uses hands. The Puppeteer's native language sounds like highly complex orchestral music, but they seem to be able to reproduce human language without difficulty or device, as well as the Heroes' Tongue (Kzinti), suggesting their vocal arrangement may resemble a pair of avian-like syrinx rather than vocal cords. The sobriquet "Pierson's" comes from the name of the human who made first contact in the early 26th century in the Known Space timeline. According to the Niven story The Soft Weapon, Pierson was a crewman aboard a spaceship at a time when there was a camp revival of the ancient Time for Beany TV show featuring Cecil the Sea-Sick Sea Serpent, an animated character based on a hand puppet; Pierson accordingly described the alien he had met as a Puppeteer, given some resemblance of the head and neck with Cecil. Puppeteers dealing with humans usually give themselves the names of centaurs and other figures in Greek mythology, such as Nessus, Nike and Chiron. Puppeteers' names for themselves are highly complex, and unpronounceable by humans. The group name they use for their own species translates as "Citizens".

Biologically, Puppeteers are highly intelligent herbivores; a herd animal, Puppeteers prefer the company (and smell) of their own kind. Their cycle of reproduction is similar to that of Earth's digger wasps: the Puppeteers consider themselves to have three genders (two male, one female): the two "male" genders are the equivalent of human female and male (one has an ovipositor, the other produces sperm) and the "female" is a (non-sentient) parasitized host into which the ovum and spermatozoon are deposited.

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