The 2015 season was the Hawthorn Football Club's 91st season in the Australian Football League and 114th overall. Hawthorn entered the season as the two-time defending AFL premiers, having won back-to-back AFL premierships. Hawthorn won their third consecutive AFL premiership, fifth AFL premiership, and thirteenth premiership overall, defeating West Coast 107–61 in the Grand Final. Hawthorn became the first team to win five premierships in the AFL era. Hawthorn became just the second team in the AFL era to win three-consecutive premierships; joining the Brisbane Lions (2001–2003); and the sixth team in VFL/AFL history to win three consecutive premierships; joining Carlton (1906–1908), Collingwood (1927–1930), and Melbourne (twice; 1939–1941, 1955–1957). Alastair Clarkson won his fourth premiership as coach, tying with Leigh Matthews for most premierships won in the AFL era. Clarkson also surpassed John Kennedy Sr. and Allan Jeans (3) for most premierships won as coach of Hawthorn. Luke Hodge joined Michael Voss as the only players to captain three premierships in the AFL era. Grant Birchall, Shaun Burgoyne, Luke Hodge, Jordan Lewis, Sam Mitchell, Cyril Rioli, and Jarryd Roughead all won their fourth premierships, tying with Martin Pike for the most in the AFL era. Shaun Burgoyne played in his sixth AFL Grand Final, tying with Martin Pike for the most appearances in the AFL era.

The 2015 AFL season was the 119th season of the VFL/AFL competition since its inception in 1897; having entered the competition in 1925, it was the 91st season contested by the Hawthorn Football Club. The Melbourne Cricket Ground once again acted as Hawthorn's primary home ground, hosting six of the club's eleven home games,^[1] with four games played at their secondary home ground, Aurora Stadium in Launceston, and one played at Etihad Stadium in Round 21. The four matches at Aurora Stadium were against the Western Bulldogs, Gold Coast Suns, Fremantle and the Brisbane Lions in rounds 3, 9, 15 and 22 respectively,^[2] while the one home game at Etihad Stadium was against Port Adelaide in Round 21. The club played Geelong, Essendon, Port Adelaide, Sydney and Carlton twice during the regular season, and travelled interstate five times (twice each to Sydney and Adelaide, and once to Perth).^[1]

Major sponsors Tasmania and iiNet continued as the club's two major sponsors,^[3][4] while Adidas continued to manufacture the club's on-and-off field apparel.^[5]

Alastair Clarkson continued as the club's head coach for the eleventh consecutive season, while Luke Hodge continued as the club's captain for the fifth consecutive season. Both have held their respective positions since 2005 and 2011, respectively.

During the 2014 off-season, the Hawks acquired the services of Melbourne's James Frawley via the free agency system,^[6] as well as those of Greater Western Sydney's Jonathan O'Rourke during the trade period.^[7] 200-gamer Brad Sewell announced his retirement shortly after the end of the club's 2014 season, in which the club won their 12th premiership but for which he was overlooked.^[8] In addition, Mitch Hallahan, Kyle Cheney and Luke Lowden were all traded away from the club,^[9] while Jordan Kelly, Derick Wanganeen and Ben Ross were all delisted.^[10]

The following lists all player changes between the conclusion of the 2014 season and the beginning of the 2015 season.

The club played three practice matches as part of the 2015 NAB Challenge, and were played under modified pre-season rules, including nine-point goals.

• 2015 All-Australian team selection: Josh Gibson, Sam Mitchell, Cyril Rioli
• Norm Smith Medallist: Cyril Rioli

• Round 1: Sam Mitchell kicked Hawthorn's 170,000th point in the VFL/AFL
• Round 17: Hawthorn inflicted Carlton's heaviest AFL defeat, winning by 138 points. The Hawks' score of 27.11 (173) was also the highest score posted during the AFL season.

• Round 1: James Frawley – first AFL game for Hawthorn (previously with Melbourne)
• Round 2:
  • James Sicily – AFL debut
  • Jonathan O'Rourke – first AFL game for Hawthorn (previously with Greater Western Sydney)
• Round 3:
  • Jarryd Roughead – 450th AFL goal
• Round 7:
  • Grant Birchall – 200th AFL game
• Round 8:
  • Ben Stratton – 100th AFL game
• Round 9:
  • Luke Breust– 100th AFL game
  • Daniel Howe – AFL debut
• Round 10:
  • Taylor Duryea – 50th AFL game
  • Alastair Clarkson – 150th win as head coach
• Round 14:
  • Luke Breust – 200th AFL goal
• Round 15:
  • Luke Hodge – 100th AFL game as Hawthorn captain
  • Paul Puopolo – 100th AFL game
• Round 16:
  • Isaac Smith – 100th AFL game
  • Cyril Rioli – 200th AFL goal
• Round 17:
  • Jack Gunston – 200th AFL goal
• Round 18:
  • Alastair Clarkson – 250th AFL game as head coach
• Round 19:
  • Cyril Rioli – 150th AFL game
• Round 21:
  • Hawthorn's 1,900th game of VFL/AFL football.
• Round 22:
  • Jack Gunston – 100th AFL game
• Semi Final:
  • Matt Suckling – 100th AFL game
• Preliminary Final:
  • Brian Lake – 250th AFL game

• italics denotes ineligible player