A dour game saw both sides fail to raise their games, although Rotherham's defence was impressive throughout.
The best move of the game led to the goal, a deep cross from the left was swung in and Lee beat his marker to plant a towering header into the top corner.
The visitors did brilliantly to keep Wycombe out, although the five minutes of added time caused Ronnie Moore's side some anxiety.
Elsewhere, Swindon Town helped allay their relegation fears with a hard-fought 1-0 win over Colchester United.
The only goal of the game came from on-loan star Michael Reddy in the 28th minute as he cashed in on a goalmouth scramble to toe-poke the ball home.
Bury beat Wrexham in Wales for the first time in their history with a goal from Jon Newby (pictured) in injury time.
The former Liverpool striker pounced to hit his fourth goal for his new club on the day he signed permanently for The Shakers.
Bristol Rovers' clash with Peterborough United was called off because of adverse weather conditions making the pitch dangerous. Click below for the relevant report:
Colchester United 0 Swindon Town 1
Wrexham 0 Bury 1
Wycombe Wanderers 0 Rotherham United 1
