The investors were the only bidders for Ciudad Real airport, south of Madrid, completed during Spain's boom years.
But it is not clear if the sale will go ahead as another buyer could still step forward outside of the auction process, the BBC reported.
The winning bid was made by a Chinese-led consortium of investors. The group, Tzaneen International, says it wants to make the airport an entry point into Europe for Chinese companies.
Ciudad Real airport, located 235km south of Madrid, was meant to be an alternative to Madrid's Barajas airport.
It cost more than 1 billion euros to built. It opened in 2008 but went bankrupt and closed in 2012.
There is still a possibility that another buyer could meet the minimum price of 28 million euros set by the receiver for the sale to go through before the end of September.
The central Spanish airport has a capacity for 2.5 million passengers per year.
It is one of a number of "ghost airports" constructed during Spain's building boom that did not attract enough passengers.
A similar fate has befallen Castellon airport in the east. It opened in 2011 but has not received a single flight, the report said.
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