Beckford scored a brace in Leeds' win over The U's, although a hamstring injury prevented him from playing in their Johnstone's Paint Trophy semi-final with Carlisle on Tuesday.
The former Wealdstone striker admitted he was taken aback to win the fans' award for back-to-back months.
"I'm delighted to win the award," said Beckford. "It's nice to know that so many fans have voted for you."
Whites boss Simon Grayson is pleased Beckford, who has 18 goals from 26 League One starts this season, has been rewarded for his efforts.
"I'm delighted to see Jermaine rewarded again for all his efforts with this award," added Grayson. "The fact that it is voted for by the fans makes it all the more special and it shows how highly he is regarded by the Leeds supporters.
"Jermaine has played a big part for this club since I came here and it was a boost in January when he decided this is where he wants to stay and help finish the job off that he has played such a big part in."