DNI may stand for:
Andrzej Piaseczny (born Pionki, 6 January 1971) more commonly known as Piasek, is a Polish singer.
Piasek represented Poland in the Eurovision Song Contest 2001 with his up-tempo dance song "2 Long". He finished 20th from a field of 23 participating countries. The song received 2 points from Sweden, 3 points from Slovenia, 5 points from Germany and 1 point from Denmark.