Sir Gary Verity said giant “land art” projects planned by schools and community groups would generate publicity “that you literally could not put a price on”.
Projects created by communities on the route of the three-day race, which begins on Friday, include an enormous “tunny” fish in Scarborough and a Bradford Boar on a bike in Keelham.
In Driffield, hundreds of schoolchildren will make a 6,000 sq ft “human bicycle”, which will give the illusion of movement as the race passes by.
The artworks will be picked up by aerial TV cameras and shown to Britain and 167 other countries.
On the third day of the race, the West Yorkshire villages of Baildon and Queensbury will spell out their names in banners nearly 50m long and 10m high, and a giant sheep with red spots will be painted on the roof of the Woolshops centre in Halifax.
Sir Gary said: “This is the biggest event in Yorkshire this year, by some margin. There is no other free event in the world where you can get so close to so many world-class athletes.
“The land art projects have involved massive amounts of work, and the TV helicopters will show them to the world.”
The race will also showcase the new road bridge at Tadcaster, opened earlier this year to replace the one washed away in the Boxing Day floods of 2015.
Yorkshire has enjoyed record years for tourism, following the 2014 Grand Depart of the Tour de France and the Tour de Yorkshire that followed as its legacy.
Sir Gary said: “The economic benefit of the event is significant but it is also about bringing communities together. People are really getting together to help promote their areas.
“The television exposure is crucial to all this. You literally couldn’t put a price on this sort of coverage.”