Maghoma picked out the top corner with a sublime finish from the edge of the box, giving Harry Isted absolutely no chance.
The Brentford loanee has scored eight goals in all competitions this season – seven of those coming in the league.
“I wanted to score more goals this season and playing in this team has given me lots of opportunities,” he said.
“This one has probably been the best of them, and I’m delighted it was chosen to win the award.
“I’d like to thank the judges and the fans who voted for it and hopefully there are still one or two more goals to come this season to help us win the games we need to secure promotion.”
Maghoma beat off competition from Reading’s Femi Azeez, Shrewsbury’s Jordan Shipley and Wycombe’s Beryly Lubala to win the prize.
Sky Sports pundit and Goal of the Month judge Don Goodman added: “We had another Goal of the Season shout in League One’s competition.
“Paris Maghoma showed exceptional trickery and balance to craft space on the edge of the box!
“He seemed to have most of the Charlton defence on a piece of string going one way and then the other before curling a beautiful finish into the top corner. The Charlton defence might not forget this one in a hurry.”
Wanderers have now had back-to-back winners after Zac Ashworth claimed the award in January following his goal in the 4-1 victory at Carlisle.
Elsewhere, Southampton midfielder Joe Rothwell won the Championship prize and the League Two award went to Barrow forward Cole Stockton.
