Ahmad bin Aqeel al-Khatib, the General Entertainment Authority chief, said the money will come from both the government and the private sector.
More than 5,000 events are planned for 2018 said the authority earlier this week.
"We are already building the infrastructure," Khatib said, adding that an opera house was already in the works. "God willing, you will see a real change by 2020."
Earlier in the month
, construction contracts were awarded for five palaces in the development of a huge $500 billion megacity.
The ambitious project, announced by Crown Prince Mohammed bin Salman
in October last year, will establish a 26,500 square km (10,230 square mile) zone dedicated to several industries, including biotechnology, water, food, energy, water and entertainment.
Saudi's young crown prince has been at the helm of a programme of reforms - known as Vision 2030
- looking to modernise the country.
The ambitious young leader aims to revive the Saudi economy by diversifying it away from its reliance on oil exports, as well as driving up domestic spending through the creation of cinemas, music venues and theme parks.
Last month, John Travolta visited Riyadh
to give a talk to Saudi film-lovers on his eminent Hollywood career.
The kingdom also announced its intention to invest $500 million dollars in Hollywood
agency Endeavour, which manages the likes of Emma Stone and Jake Gylenhaal.
Many have welcomed the reforms that promise to breathe life back into Saudi's virtually non-existent popular cultural scene.
The shake-up has been especially welcomed by the kingdom's youth, who make up more than half of the entire population. However, some are anticipating a backlash from the country's conservative clerics
Critics also warn of a 'public relations coup' saying that bin Salman's contradictory programme of authoritarian-led liberalisation has been accompanied by a crackdown of social media witch hunts of alleged traitors and arrests.