Toni Petteri Lydman (born 25 September 1977) is a Finnish former professional ice hockey defenceman. He first played competitively in his native Finland with Tappara, and HIFK of the SM-liiga before enjoying a lengthy career in the National Hockey League with the Calgary Flames, Buffalo Sabres and the Anaheim Ducks.
Lydman was drafted by Calgary in the fourth round, 89th overall at the 1996 NHL Entry Draft. He spent four seasons playing in Finland's SM-liiga for Tappara in Tampere and HIFK in Helsinki before making his NHL debut for the Flames in the 2000–01 NHL season.
His best season came in 2001-02, when he scored 28 points on 6 goals and 22 assists, tying for fifth for his team in assists and sixth in points scoring. In the 2002–03 NHL season, Lydman led his defense in points with 26 and managed to remain injury-free the whole season, only missing one game due to illness. Calgary made it to the Stanley Cup finals in the 2003–04 NHL season, but Lydman missed most of their playoff campaign due to injury. During the 2004–05 NHL lockout, which wiped out the entire 2004–05 NHL season, Lydman returned to Helsinki for HIFK but only managed to play eight games.