The centre will open in the fourth quarter after a delay of more than a year amid construction problems.
Within the budget, 190 million baht will be for equipment and facilities such as waste storage and the rest for hiring a company to manage the centre for one or two years.
The Tourism Authority of Thailand (TAT) will supervise the management selection process.
Suwat Sidthilaw, the ministry's permanent secretary, has insisted the centre be managed by the private sector, not the ministry.
He said the TAT should look at the terms offered by each management company such as return on investment and management duration.
"We welcome all professional venue managers, but we cannot allow them to survey the centre yet," said Mr Suwat.
In another development, the TAT plans to merge the Thailand Travel Fair (TTF) and the Thailand Travel Mart (TTM Plus).
The single big co-event will be called the World Tourism Expo in 2014.
Thawatchai Aranyik, the TAT's deputy governor for domestic marketing, said the World Tourism Expo will see two major changes. First, business negotiations at TTM Plus will be included at the TTF.
"We agreed to merge the two events and organise them into a concept to attract new-generation travellers," said Mr Thawatchai. "Old-style tourism fairs may not attract these young tourists."
After the merger, there will be business negotiations with 300-400 Thai travel agents and foreign buyers. International tourism organisations and outbound tour operators will present products to foreign buyers and Thai visitors. The TTF will be organised for consumer fairs for the general public.
The World Tourism Expo will cost about 500 million baht and be held at Impact Muang Thong Thani.