The body of the Prime Minister's constituency chairman Christopher Shale was discovered by police in the VIP area of the Glastonbury festival at around 9am Sunday.
Mr Shale, 55, is chairman of the West Oxfordshire Conservative Association
He is believed to have died from a heart attack but the official cause of death has not yet been confirmed.
A police cordon has been thrown up around the backstage toilet and shower area.
Many celebrities had been staying within the cordoned off area and security was especially tight prior to the arrival of Sunday night's headline act Beyonce.