He joined Lille for just 12m euros, but Osimhen has seen his value almost triple following a brilliant start to his Ligue 1 career.
The 20-year-old signed for Les Dogues in June for a reported fee of 12m euros, but he is now valued at 30m euros.
According to a report from Transfer Market, who did a study on the value of all Ligue 1 players, Osimhen had the highest increase in value, while Neymar saw a drop in his value.
The Super Eagles star is currently priced at 30m euros which is almost three times more than what Lille paid for him back in June.
The Nigerian international has been linked with a move to Spurs, Chelsea and Liverpool ahead of the January transfer window.
However, any team hoping to acquire his services will have to pay a sum in the region of 30m euros, although it is unlikely Lille would let him leave in January.
Meanwhile, Neymar who is the most expensive player in the world saw his price drop from 220m euros PSG paid for him to 160m euros.
His PSG teammate, Edinson Cavani drops out of the top 10 most valuable players following a difficult season. Lyon are the biggest winners as three of their players fall into the top ten.
The trio of Memphis Depay (25, +€10m to €55m), Moussa Dembélé (23, +€10m to €40m), and Houssem Aouar (21, +€5m to €50m) are all included in the top ten most valuable players in the French topflight.