Welbeck was given a starting berth in the 2011 FA Community Shield match at Wembley Stadium on 7 August 2011. United won the match 3–2, having trailed rivals Manchester City 2–0 at half time. He started alongside Wayne Rooney in the first league match of the 2011–12 Premier League season away to West Bromwich Albion; he was substituted in the 65th minute, to be replaced by Dimitar Berbatov. On 22 August, Welbeck scored the opening goal of the match against Tottenham Hotspur, heading in a cross from Tom Cleverley from nine yards to score in the 61st minute. He then provided an assist for Anderson in the 76th minute to make the score 2–0 before being substituted. The match ended in a 3–0 win for United. Welbeck opened the scoring in an eventual 8–2 win over Arsenal. From outside the box, Anderson chipped the ball into Welbeck and he headed it over Wojciech Szczęsny. However, Welbeck had to leave the field early with a pulled hamstring which, consequently, ruled him out for several weeks.
Welbeck scored twice in a Champions League group match against Basel on 27 September; the match ended 3–3. Welbeck scored again in the next match, a 2–0 home win over Norwich City, after coming on as a second-half substitute. He exchanged passes with Park Ji-sung before sweeping low into the bottom corner to seal the win. On 21 December 2011, Welbeck opened the scoring at Craven Cottage in a 5–0 win against Fulham. He met Nani's cross and steered the ball in with his left foot. On 8 January 2012, Welbeck scored the second goal in a 3–2 away victory against Manchester City at the City of Manchester Stadium in the FA Cup third round. Patrice Evra made a half-cleared cross, which Welbeck volleyed into Costel Pantilimon's bottom corner. On 14 January, it was reported that Welbeck would sign a long-term contract at Old Trafford. On 22 January, Welbeck scored the winning goal in the 81st minute in a 2–1 away victory at the Emirates Stadium over Arsenal—his third goal in three matches. His impressive performances throughout the 2011–12 campaign earned him a place on the shortlist for the 2012 PFA Young Player of the Year Award, which was won by Tottenham Hotspur defender Kyle Walker.
He played in England's deciding UEFA Euro 2012 qualifier against Montenegro on 7 October 2011, coming on as a substitute for Theo Walcott in the second half. On 29 May 2012, Welbeck was listed as a part of the confirmed 23-man squad for Roy Hodgson's England squad for UEFA Euro 2012. On 2 June 2012, he scored his first goal for England in a 1–0 win against Belgium, with a chip over goalkeeper Simon Mignolet after collecting a through ball from his Manchester United teammate Ashley Young. On 15 June 2012, Welbeck scored a backheeled winning goal in the 79th minute as England beat Sweden 3–2 in UEFA Euro 2012 in Kiev.