The three-times champion jockey has enjoyed another hugely-successful year and picked up the award - which he also won in 2015 - at a presentation event in Hong Kong on Friday.
After winning eight of the top 100 Group/Grade One races the competition is calculated on, Dettori topped the standings with 128 points to join Ryan Moore - victorious in both 2014 and 2016 - as a dual winner.
Finishing second was Oisin Murphy with 114 points, while Moore was a further two points adrift in third.
Dettori said: "I've had a phenomenal season. To have these kind of horses in the same year is phenomenal. A lot of thanks goes to the owners and John Gosden, who is an amazing trainer and we have done so well together.
"John is a genius of a trainer and what I have achieved this year is really down to him.
"There are lot of excellent jockeys out there, especially the young generation. There is not much room for error and racing in every angle of the sport really has gone up a few notches.
"Like any sport you have to be on your A-game, as it is very tough - but competition makes the sport even better."
Looking ahead to 2019, the ever-popular Italian is unsurprisingly excited about continuing his relationship with dual Prix de l'Arc de Triomphe heroine Enable.
He added: "I am looking forward to having Enable for another year to showcase around the world and try and win a third Arc which has never been done before.
"Next year is another new page. I will try and win every big race and try and become the best jockey in the world again."
