The Colombian has scored 28 goals in all competitions this season, including 16 in the league to help Steven Gerrard’s side to the second spot in the log.
His impressive form has drawn comparison with the 22-year-old who put in laudable performances when he played for the Bhoys, subsequently earning him a move to Lyon before the commencement of this season.
Dembele who joined the Scottish side from Fulham in June 2016 scored 51 goals to help the Celtic Park outfit win two Premiership titles, two League Cup and two Cup titles.
However, the former Scotland international is of the opinion that with Morelos delivering in a relatively less talented set-up, he is the better player.
“They are different players,” McFadden told SPFL Matters per Daily Star.
“Dembele when he came up from Fulham, he hit the ground running, he was part of the invincible side, he won trophies.
“But he played in a very good side. Morelos, at the minute, certainly last season, didn't play in a very good side yet he still scored goals.
“He carried Rangers. This season, they are much improved, but he is still scoring goals.
“Dembele was part of a very strong side. He wasn't the only one scoring goals.
“Rangers have Morelos and the second top goalscorer is Tavernier on penalties.
“Morelos is doing a lot of it on his own. But he's not playing with the quality of players Dembele played with at Celtic.”