5-hour blackout on Spanish stock exchange
The benchmark Ibex 35 shot up 2.5 percent when trading began again just before 3 p.m. (1300 GMT).
An exchange spokesman, Jesus Merino, said technical problems had caused the breakdown Monday but he could give no further details.
Spain's stock market has been convulsed in recent months as investors react to the ups and downs of the country's economic crisis.
The government is desperate to avoid having to seek a sovereign financial bailout but its problems are mounting daily. Debt is rising and unemployment is near 25 percent.