The 19-year-old saw off competition from Leeds Rhinos full-back Jack Walker and St Helens prop Matty Lees to lift the trophy at an awards ceremony in Manchester where St Helens full-back Ben Barba was named Steve Prescott Man of Steel.
Trueman missed Friday’s 14-0 semi-final loss at Wigan Warriors having broken his hand a little over a week ago, an injury that will also deny him the chance to tour Papua New Guinea with England Knights.
But he has enjoyed a superb campaign, relishing the added responsibility and, indeed, blossoming when Castleford’s England scrum-half Luke Gale – last year’s Man of Steel –missed four months of action due to knee surgery.
It was a sign of how much Trueman has developed that Tigers badly missed his guile, control and kicking quality in the defeat at Wigan that ended their season.
He becomes the third Castleford player to claim the award after Joe Westerman (2008) and Daryl Clark (2014).
Gale came back late in the season, but was last night ruled out of the forthcoming series against New Zealand after a setback in his rehabilitation from that ongoing knee issue.
England will name a replacement shortly.
Australian Barba took the prestigious Man of Steel as Super League’s top player after collecting more votes from fellow players than team-mate James Roby and Wigan’s John Bateman.
Wigan’s Shaun Wane, who leads them into Saturday’s Grand Final against Warrington in his last game before switching to Scotland RFU, was named Coach of the Year.
Castleford’s Georgia Roche became the inaugural winner of the Woman of Steel award while Gale took Top Gun for the best kicking percentage (87.27 per cent with 48 goals out of 55 attempts) and Tigers hooker Paul McShane was Hit Man with 1160 tackles, more than any other player.
Leeds Rhinos won the Foundation of the Year award following success for their women’s team – who will play in the Women’s Super League Grand Final on Saturday against Wigan - plus the launch of a women’s under-19s team, the launch of a PDRL side, and a first victory in the Wheelchair Rugby League Grand Final in Kent.
Wakefield Trinity’s Tongan centre Bill Tupou was the leading Metre Maker with 4,114 while Warrington earned Club of the Year, not only for reaching both the Grand Final and Challenge Cup final at Wembley in August, but also for their equally strong off-field efforts with emphasis on growing crowds, fan engagement and their work in the community.