As a player, Cleary was a goal-kicking fullback who played club football in Australia and New Zealand, setting a new record for most points scored in a season during the 1998 NRL Premiership.

He started his first grade career with the Manly-Warringah club in 1992 playing two games before getting his chance after the team's first choice fullback Matthew Ridge suffered a season-ending injury in mid-1993.

[citation needed] In his 15 first grade games for Manly, Cleary scored eight tries and kicked 50 goals (from 71 attempts for 70.4%) for a total of 132 points.

[4] With Ridge set to return in 1994 Cleary signed with Manly's local rivals the North Sydney Bears for 1994 and 1995 seasons where he mainly played in the centres due to the emergence of fullback Matt Seers.

[8] After leaving the Warriors, Cleary originally intended to join the Huddersfield Giants in the Super League but instead retired to take up a coaching opportunity with the Sydney Roosters.

On 11 August 2018 Cleary released a prepared statement ending speculation that he would leave the Wests Tigers to coach Penrith.

"[18][19] On 29 October 2018, the Penrith Panthers confirmed the return of Ivan Cleary as head coach, on a 5-year deal, beginning in 2019.

[20] Ivan linked with his son Nathan Cleary and began his second stint as head coach at the Penrith Panthers.

Cleary's second spell in charge at Penrith got off to a bad start with the club winning only 2 of their first 10 matches leaving the team bottom of the table.

Following the full time siren, angry Wests fans shouted abuse at Cleary who was inside the coaches box.

After defeating both the Parramatta Eels and the Melbourne Storm, Penrith qualified for the 2021 NRL Grand Final being held at Suncorp Stadium on 3 October 2021.

[28] On 24 February 2024, Penrith would lose the 2024 World Club Challenge final against Wigan 16–12 at the DW Stadium in controversial circumstances.

Melbourne would be left scoreless in the second-half to reverse the result of 2020 and hand Penrith and Cleary their fourth Premiership in a row.