The legendary cyclist was not picked to be part of his team's squad for the famous race.
This will be the first Tour de France Cavendish has missed since 2007.
Much like his hero, five-year-old Evan was very disappointed by the news.
Evan's mum Louise tweeted a picture of her upset son with a special message from Evan.
"It's ok Cav because I still want to ride my bike with you," it said.
Mark was clearly touched by Evan's message and he decided to bring a smile to his fan's face by going on a bike ride with him in Nottinghamshire.
After their special day together, Cavendish tweeted Evan this lovely message: "It was an absolute pleasure Evan. Couldn't bear to to see you sad. I knew a bike ride would cheer us both up."