Bothroyd, this week named in Fabio Capello's provisional England party, is gunning for his first senior international call-up.
And based on this showing he could well be set to swap Glanford Park for Wembley Stadium having grabbed a brace to take his tally for the season to 15 in 16 games, while also providing an assist for Michael Chopra.
Cardiff's first-half dominance was unquestionable, with Bothroyd, 28, breaking the deadlock from close range with just 54 seconds on the clock and Chopra adding a second after nine minutes in similar circumstances.
Bothroyd's header doubled his tally for the afternoon before Kevin McDonald reduced the deficit just prior to half-time.
Yet it was firmly a game of two halves and Scunthorpe had the visitors on the ropes after the break, Dany N'Guessan making it 3-2, before Seyi Olofinjana made certain of the points.
Victory sends Cardiff back to the top of the table, and they could be set for further celebration in the form of the Welsh club's first ever England international.
The Iron were handed a mountain to climb early on as the Bluebirds, boosted by the return of previously rested Craig Bellamy, broke the deadlock with their quickest goal of the season.
Chopra cut inside on the right and his shot was parried by Joe Murphy, but only straight into the path of former Wolves and Coventry marksman Bothroyd, who converted easily.
The visitors were rampant inside the opening stages, with Kevin McNaughton and Bothroyd both going close from distance.
And it was the in-form 6ft 3in striker who returned the favour for Chopra to put Cardiff two goals up, firing a low cross-shot across goal which left the former Sunderland marksman with a simple tap-in.
A shell-shocked Scunthorpe finally got some kind of foothold in the game but Cardiff were always looking more dangerous in the final third, and it was no real surprise when they added to their tally in the 34th minute.
Bellamy this time claimed the assist, whipping over a free-kick which Bothroyd headed downward and into the net from 12 yards.
On-loan West Ham striker Freddie Sears dragged his effort wide in response, but Scunthorpe did pull one back just before the break courtesy of McDonald's well-taken finish.
Iron keeper Murphy produced a superb double save to deny Bothroyd his hat-trick shortly after the restart when it looked as though he would be walking away with the match ball.
Despite that, the hosts were putting up a much better showing than their first-half display and Tom Heaton was called into action to deny Jonathan Forte as Ian Baraclough's men threw everything forward.
N'Guessan deservedly pulled them within touching distance in the 73rd minute with a powerful header, but any hope of an unlikely point was shortlived as Olofinjana diverted Jason Koumas' goalbound effort home to extend Scunthorpe's unwanted home record to one win in nine league games.