Mr Prabowo has been nominated by his Great Indonesia Movement party (Gerindre) and five other parties.
My Widodo is backed by the Indonesian Democratic party of Struggle, which won the April 9 legislative elections, and three other smaller parties.
Styling himself as a robust and decisive leader, My Prabowo uses nationalist rthetoric and invokes his military background to appleal to voters.
He has vowed to protect the country's natural resourcer from being exploited by foreign companies, and to stop corruption.
Mr Widodo, a former furniture exporter, is known as a politician with a simple lifestyle and common touch, and as a successful governor in the capital Jakarta. dpa