Nicolai Vollquartz (born 7 February 1965) is a Danish football referee.
He was born in Viborg.
He was promoted to the FIFA referees list in 1999 and took charge of his first UEFA Cup match – a first round tie between Rapid Bucuresti and Liverpool – on 14 September 2000.
His UEFA Champions League debut came a year later, with a second qualifying round match between Wisla Kraków and Skonto.
It was another five years before he officiated a Champions League group stage match – the Group B match between Sporting CP and Spartak Moscow on 5 December 2006 – but it was to be his only experience in the group stage.