The newly named course point came as the Isle of Man Government redesigned and replaced the existing directional boards and mile markers around the 37¾-mile course.
McGuinness first competed on the Isle of Man in 1996 and has 19 race victories to his name, including two last year. He is also the outright lap record holder with a lap of 131.578mph, he set in 2009.
McGuinness joins other great names from motorcycling history in having sections of the course named after them, including Giacomo Agostini, Geoff Duke, Jimmy Guthrie, Mike Hailwood and Joey Dunlop. The new-look signs featuring names of famous TT riders also include some individual artwork reflecting the rider's iconography.
The point of the course which will now be known as McGuinness's is at Shoughlaigue, the fast run down from Handley's Corner before the top of Barregarrow.
It is his favourite part of the course and one where he believes he can gain time on his rivals.
The sign at McGuinness’s features the infamous voodoo artwork that has adorned his helmets for many years.