Daniel or Dan Ryan may refer to:

• Daniel Ryan (figure skater) (died 1961), American ice dancer who competed with partner Carol Ann Peters
• Daniel Ryan (actor) (born 1968), English actor and writer
• Daniel L. Ryan (1930–2015), American prelate of the Roman Catholic Church
• Daniel J. Ryan (1855–1923), Republican politician in Ohio
• Dan Ryan, Sr. (died 1923), American politician from Chicago, Illinois
• Dan Ryan Jr. (1894–1961), his son, American politician
• Dan Ryan (electronic sports player) (born 1986), American electronic sports player
• Daniel Ryan (Tasmanian politician) (1870–1953), Australian politician
• Daniel Joseph Ryan, American politician in the Massachusetts House of Representatives
• Daniel Ryan (Queensland politician) (1865–1952), member of the Queensland Legislative Assembly