Terry, who died in January at the age of 77, hosted the BBC’s Eurovision coverage from 1971 until 2008, when Graham took the reins.
But despite Terry’s kitsch style being a hit with viewers, he has been accused of “spoiling” the contest’s reputation by Swedish producer Christer Bjorkman.
When asked why Brits don’t take the competition seriously, he told the Mirror: "There are several reasons, one is Terry Wogan himself.
However, Graham says Terry will forever be connected to the Eurovision after making it his own.
Graham told the Mirror: “Sir Terry Wogan will always be associated with Eurovision.
“I think this year will be bittersweet because we will all be thinking of Terry and I am sure I will say a few words about him as the night goes on as it is a night that will forever be associated with Terry Wogan.”
The 53-year-old chat show host added that he would be “raising a glass” to his predecessor during this year’s show.
“It has all worked out very nicely as Swedish people in the arena will be cheering their song in the stadium as everyone back in the UK will join me and cheers the memory and legacy of Sir Terry Wogan.”
This year the UK is represented by former ‘The Voice’ contestants Joe Woolford and Jake Shakeshaft with their song, ‘You're Not Alone’.
The final, which will be shown on BBC One, will be hosted by last year’s winners Sweden, from Stockholm's Ericsson Globe, on 14 May.