The updated graphics will give the brand a more modern look while retaining its iconic identity, a spokeswoman said.
The new look will be supported by a £2.3 million media spend that includes a TV ad screening in the run-up to Christmas.
Two limited-edition flavours - Dazzling Dark Mint made with real peppermint oil, and Cosmic Toffee Crunch - will also be rolled out.
Dave McNulty, convenience sales customer director, said: " It is important to re-invigorate brands to attract new customers and excite existing fans."
Terry's Chocolate Orange is available in packs of 12, retailing at £2.39 for a 175g ball.