Lieutenant Walter Baxter was a male Human Starfleet officer who served under Captain Kathryn Janeway aboard the USS Voyager when it was pulled into the Delta Quadrant in 2371.

As a workout enthusiast, Baxter suffered an injury that year while exercising in the ship's gymnasium. In sickbay, Baxter directed all his questions to Kes, and was quite dismissive of The Doctor, questioning whether or not a hologram could perform the duties of a flesh-and-blood doctor, such as perform surgery. Later, when Baxter reported to sickbay again for another workout-related injury, The Doctor informed him that, if he were to suffer another injury due to failure to restrain himself during workouts, The Doctor would be forced to discuss the matter with Baxter's superior officer, a statement which forced Baxter to acknowledge The Doctor as the chief medical officer. (VOY: "Eye of the Needle")

When Voyager discovered a Human settlement on a planet in the Delta Quadrant, Captain Janeway decided to let any crewmember who so desired to remain behind. Theorizing about which members of the crew would decide to leave the ship, she speculated that Baxter would be one of them, describing him as a "risk-taker" who would be eager to take on the challenge of building a new life on the planet. Chakotay hoped he wouldn't leave, as he found the officer to be a good man. Neither Baxter nor any other crew member wound up leaving. (VOY: "The 37's")

Later that year, Baxter was exercising yet again in the gymnasium, when Voyager encountered a spatial distortion ring. Attempting to reach the cargo bay, Baxter found that he could not navigate around the ship due to the constant reconfiguration Voyager suffered as a result of contact with the ring, and ended up in the transporter room, where he was encountered by Lieutenant Torres, who was trying to reach engineering. (VOY: "Twisted")

Baxter was played by Tom Virtue and wore a command division red uniform in his first appearance, but was in security and an operations division yellow uniform in his second appearance. His first name was referenced in "The 37's", an episode he did not actually appear in.