The case pertains to setting up of power stations at inflated costs to meet acute electricity shortages when Ashraf was minister for water and power from 2008 to 2011.
Judge Muhammad Bashir of the Islamabad-based accountability court rejected the pleas of the defendants and charge sheeted the former prime minister and his associates, Dawn News reported.
Other prominent persons indicted in the case include former finance minister Shaukat Tareen, former federal secretaries Ismail Qureshi and Shahid Rafi.
The accountability court dismissed requests filed by Tareen and Qureshi that their names be dropped from the case.
NAB has been investigating 12 Rental Power Projects (RPPs) cases in which nine firms reportedly received more than Rs 22 billion as mobilisation advance from the government to commission the projects, but most of them were accused of failing to set up the plants.
The bureau has already recovered Rs 13 billion in the case.