The upper house of the Spanish parliament ratified the Lisbon Treaty on Tuesday after the Deputy Congress gave its approval with a large majority, according to Novinite.
The Senate`s ratification makes Spain the 23th out of 27 member countries to back the document.
The Lisbon Treaty, which is designed to improve the EU`s decision-making process, needs to be ratified by all of the bloc`s 27 member states.
The treaty was designed to replace the EU constitution, which was rejected by French and Dutch voters in 2005.
Ireland, the only country to hold a referendum over the Lisbon Treaty, rejected it with 53.4 percent of the voters saying "no."
On Tuesday French president Nicolas Sarkozy commented that Ireland would have to hold a second referendum on the new EU treaty after last month`s rejection.
Mr Sarkozy, who took over the EU presidency on July 1, travels to Dublin on Monday aiming to come up with a solution to the crisis sparked by the Irish result.