"Police have arrested 14 people and freed 24 victims holed up in apartments in inhumane conditions," the police said in statement.
The victims "had to remain available 24/7 for clients to whom they also had
to offer all sorts of drugs."
The network mainly found its victims during the "Miss Trans" contest held in Venezuela, police said.
The victims were not aware they were going to Spain to become prostitutes, and were tricked with other enticements.
The network "paid for breast implants and the cost of the trip", police said.
But once they arrived their papers were taken away and they were forced into prostitution to reimburse a debt of €15,000 ($17,700).
One of the groups in the network, led by an Italian and a Spaniard, exploited transsexuals kept in an apartment in Barcelona, while another group ran prostitutes in Palma on the island of Majorca.