Neymar, who signed from Barcelona in August for a world-record fee of €222million, may have been sidelined with a broken metatarsal since February, but 19 goals and 13 assists in 20 appearances earned him the honour.
This is all a big worry for PSG if true, with Neymar's signing last summer seeming to cause tension at the Parc des Princes.
That would make him both the most expensive transfer, and the richest player in the world.
Neymar hints at PSG stay.
"Today, I am better", Neymar said.
Spanish newspaper Marca reported on Friday that the player's father and agent, Neymar Sr, had told PSG his son wanted to leave immediately.
Brazil kick off their bid for a record-extending sixth World Cup on 17 June against Switzerland, with Tite's men also pitted against Costa Rica and Serbia in Group E.
"At the moment, all I can tell you is I'm anxious about what's coming up", said the French coach, who will look to win a third consecutive Champions League title against Liverpool at the end of this month.
Zidane's side take on Celta Vigo in their final home game of the campaign on Saturday, with an away tie against Villarreal then followed by the Champions League final against Liverpool. "There will be changes for sure, but I am not thinking about that now".
Mbappe, who has scored 13 league goals, won the same award previous year when he helped Monaco to the title, and so follows Eden Hazard in claiming the young player gong two seasons running.