The news comes four days before the start of the Tour of Spain which sets out from Vilanova de Arousa in Galicia on Saturday.
"Euskaltel Euskadi is unable to continue next season," the Basque team said. "It is a sad day for Euskaltel, for the team, for the current sponsors, for the fans and for everyone who has supported this project.
"We are sad that no company or entity has decided to back this team, the oldest in the world of elite cycling."
The team said Spanish cable operator Euskaltel had increased its long-running support from 3.5 million euros (£2.97 million) a year to seven million for 2013, out of an overall budget of nine million euros, but that it could not maintain that level of backing.
The team has not been able to secure a second sponsor either locally or internationally to cover the shortfall for next year.
"From this moment on Euskaltel will start an orderly and responsible close down of the project including immediate negotiations to free up the members of the team," they said.
Contracted riders such as Samuel Sanchez, who won gold in the men's road race at the 2008 Beijing Olympics, Igor Anton and Mikel Nieve will need to find new teams next season.
(Reporting by Mark Elkington, editing by Tony Jimenez)
