The Irishman has won 22 out of his 28 fights so far, as well as being crowned the UFC champion in both the lightweight and featherweight divisions along the way.
Sadly, however, if you are a fan of McGregor that is anyway, his form hasn't been very good in the past few years having lost four of his last five fights.
His most recent bout came against Dustin Poirier at UFC 264 earlier this year, which saw him breaking his leg in the very first round while trying to get away from a punch.
However, McGregor has been recuperating well while also training hard.
The Irishman has done a lot of weight training since that night, which has seen him gain a lot of muscle on his upper body.
His size now is bigger than ever and is completely different to what he looked like during his early days.
Here, we are going to take a look at just what McGregor has put his body through throughout his career, and just how his physique has transformed to meet different weight categories along the way.
Conor McGregor's Body Transformations
McGregor made his UFC debut back in 2013 as a featherweight and weighed only 140lbs. He went on to beat Marcus Brimage via knockout in the first round.
Four years on, McGregor's stock started growing along with his muscles and number of tattoos.
He weighed 145lbs during his fight against Jose Aldo and knocked the Brazilian out after only 13 seconds to win the UFC featherweight championship.
This was McGregor's last fight in this division.
The Irishman then switched to welterweight in 2016 and lost his first fight in the division against Nate Diaz. He fought El Diablo later that year and his weight went up to 168lbs. McGregor won the fight via TKO in the second round.
McGregor then made a switch to lightweight and his weight went down to 153lbs when he fought Eddie Alvarez for the UFC lightweight championship, which he won.
The Irishman's weight was 170lbs when he fought Donald Cerrone in the welterweight division; his career heaviest.
He lost a few pounds for his lightweight fight against Dustin Poirier, which ended in defeat.
But it's not just inside the Octagon where McGregor has competed and had to undergo a transformation.
For that fight, the Irishman weighed 153lbs and competed in the super welterweight category.
So there you have it. The entire journey of Conor McGregor and how his body and physique has transformed throughout his career.
Making so many moves across weight divisions has meant that the Irishman has had to keep changing his appearance, whether that be bulking up or slimming down.
Now, he looks more muscular than ever and believes that his opponents will be scared when he returns to the Octagon.
Whenever that may be.News Now - Sport News