Up to 100 tonnes of the food waste from the three day event will be processed by Eco Composting (Eco), at its site in nearby Dorset.
There it will be treated under EU Category 3 standards and heated to 70 degrees celsius before being allowed to rest for up to four months.
After screening for plastics and other contaminants the material will be used by Eco as compost for growing turf.
Eco sales and marketing director Andy Hill said the Glastonbury contract could potentially open the floodgates to deals with other festival organisers.
The Eco facility is one of only a few in the country able to treat food waste under EU Category 3 standards. We have high hopes for this side of the business, he added.
The festival runs from 22 to 24 June and headline acts include The Arctic Monkeys, Kaiser Chiefs, The Who and Dame Shirley Bassey.