Daniel Knight "Dan" Udy (21 May 1874 – 29 July 1935) was a New Zealand rugby union player. A hooker, Udy represented Wairarapa at a provincial level, and was a member of the New Zealand national side, the All Blacks, from 1901 to 1903. He played nine matches for the All Blacks including one international.A cousin Hart Udy represented New Zealand in rugby in 1884.