The rate of unemployment in Spain, which was already the highest in the eurozone, hit 13.9% in the last quarter of 2008.
During the period, 3.2 million people were out of work - nearly 1.3 million more than in the same three months of the previous year.
The Spanish government expects it to peak at 15.9%, but the European Union says it could go as high as 19%.
The BBC reports a collapse of the property sector sparked a recession, with tourism and the service sector also weak.
Reduced production by international car companies operating in Spain has also increased unemployment.
The BBC reports there are also signs that many people are giving up looking for jobs.
In the least three months of 2008, the total workforce, the number of people working or looking for a job, fell by 400,000 having fallen by 70,000 in the previous three months.