2020–21 Ulster Rugby season

The 2020-21 season was Ulster's 27th season since the advent of professionalism in rugby union, and Dan McFarland's third season as head coach. Iain Henderson was captain. They competed in the Pro14, the Pro14 Rainbow Cup, the European Rugby Champions Cup and the European Rugby Challenge Cup.

The Pro14 season was shortened by the COVID-19 pandemic, with the two South African teams unable to compete and the playoffs reduced to a final between the winners of the two conferences. Ulster finished second in Conference A, qualifying for next season's Champion's Cup. Scrum-half John Cooney was the league's leading scorer with 115 points. Number eight Marcell Coetzee was joint top try scorer with nine, and was named Players' Player of the Season. Ulster led the league in lineouts and scrums. Cooney and Coetzee made the Pro14 Dream Team, as did fullback Michael Lowry and loosehead prop Eric O'Sullivan.

The pool stage of the Champions Cup was reduced to two matches by the pandemic. Ulster lost both and failed to progress to the knockout stage, but were entered into the Challenge Cup, making the semi-finals where they lost to Leicester Tigers. The Pro14 regular season was followed by the Pro14 Rainbow Cup, played between the winners of a European pool and the winners of a pool containing the four ex-Super Rugby South African teams. Ulster finished tenth of twelve in the European pool, and led the competition in scrums.

John Cooney was Ulster's leading scorer with 174 points. Marcell Coetzee was leading try scorer with nine. Lock Alan O'Connor was leading tackler with 242, and was named Ulster's Player of the Year. This was Coetzee's last season with Ulster: he left in April to join the Bulls. Attack coach Dwayne Peel left at the end of the season to become head coach of Scarlets.