Leeds dominated and Richard Cresswell's flicked header from an Eddie Lewis cross nearly opened the scoring.
They did go in front when Lewis drove the ball goalwards and Cresswell glanced in a header past Roman Larrieu.
The impressive Lewis then crossed for Robbie Blake to fire home before Rob Hulse made it 3-0 from the penalty spot when Mathias Doumbe fouled Liam Miller.
Leeds manager Kevin Blackwell on winger Eddie Lewis:
"In the second half I thought his quality was something else.
"We had a little chat at half-time. I wanted him to be more aggressive going forward, taking people on and crossing and he produced exactly what I asked.
"To come and quieten the crowd was the first thing I wanted to do and we did that very professionally."
Plymouth: Larrieu, Connolly (Djordjic 66), Doumbe, Ward, Barness, Buzsaky (Lasley 71), Jarrett, Wotton, Capaldi, Evans, Taylor (Derbyshire 79).
Subs Not Used: Aljofree, McCormick.
Leeds: Sullivan, Kelly, Butler, Kilgallon, Crainey, Lewis, Douglas, Derry, Miller, Cresswell, Blake (Hulse 82).
Subs Not Used: Healy, Pugh, Bennett, Richardson.
Goals: Cresswell 53, Blake 60, Hulse 86 pen.
Ref: P Taylor (Hertfordshire).