An audience of more than 3,000 is expected for the concert by Milton Keynes City Orchestra on August 14.
Firms including Yamaha, NatWest, law firms Shoosmiths and Geoffrey Leaver Solicitors, Handelsbanken and PJ Care have already signed up to sponsorship.
Orchestra chairman Marian Livingstone said: “The Proms in Campbell Park is a great partnership success for us with The Parks Trust and it keeps getting better every year.
"We are currently working on an exciting programme to bring everyone all their favourite classics and to ensure a wonderful musical evening.”
For more on the sponsorship available, contact Marian Livingstone via e-mail to email@example.com