Denise O'Sullivan (born 4 February 1994) is an Irish professional footballer who plays as a midfielder for the American club North Carolina Courage of the National Women's Soccer League (NWSL) and the Republic of Ireland national team which she has represented 80 times. She started her career with the Irish club Wilton United and joined the newly-formed Cork City at the outset of the Women's National League (WNL) in 2011. She also played for Peamount United in the County Dublin club's UEFA Women's Champions League campaigns in 2011 and 2012. In July 2013, she signed her first professional contract with Glasgow City of the Scottish Women's Premier League (SWPL).