Sprinklers doused the flames as about 100 people fled the building, Burbank Fire Marshal David Starr said. There were no reports of injuries.
Studio representatives said they were unsure which actors were present, but the stages involved were the White House situation room and a cafeteria setting.
Shortly after 8 a.m., a halogen light burst, sprinkling flaming material onto a layer of muslin that diffuses the illumination, Starr said. Sprinklers contained the flames until firefighters arrived to extinguish them.
``The stage filled completely with smoke,'' he said. ``But nobody was hurt and they were all able to exit the building. Everything went very smooth.''
He estimated that the set received $100,000 in smoke and water damage.
Production was stopped for the day but was set to resume Friday on another stage. ``The West Wing'' uses two other soundstage buildings for its sets which were not damaged by the blaze, according to the studio.
The show, which has won three consecutive best-drama Emmys, stars Martin Sheen as the fictional president. Stockard Channing plays his wife, and Allison Janney, John Spencer, Bradley Whitford and Richard Schiff co-star as his staff.
