The Berkeley Building is a 26-story, 495-foot (151 m) building located at 200 Berkeley Street, Boston, Massachusetts, USA. It is the second of the three John Hancock buildings built in Boston; it was succeeded by the John Hancock Tower. The building is known for the weather beacon at its summit, which displays distinctive light patterns as weather forecasts. The Berkeley Building is the 25th-tallest building in the city.

A weather beacon is a beacon that indicates the local weather forecast in a code of colored or flashing lights. Often, a short poem or jingle accompanies the code to make it easier to remember.