Welby may refer to:
- Entertainment
- Marcus Welby, M.D., a 1970s television series in the United States
- Places
- Welby, New South Wales, Australia
- Welby, Leicestershire, United Kingdom
- Welby, Lincolnshire, United Kingdom
- Welby, California, USA
- Welby, Colorado, USA
- People
- Justin Welby (born 6 January 1956), archbishop of Canterbury
- Piergiorgio Welby, a sufferer from muscular dystrophy, whose case stirred up a right-to-die debate in Italy
- Victoria, Lady Welby, a self-educated English philosopher of language