The Spanish senate Tuesday approved the European Union's Lisbon Treaty, confirming its ratification by the lower house of parliament last month, dpa reported.
The upper house endorsed the treaty by vote of 232-6, with two abstentions.
The senate vote came just over three weeks after the lower house backed the treaty with 97.5 per cent of the vote on June 26.
Spain has defended the continuation of the ratification process despite an Irish referendum which rejected the treaty on June 12.
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 parliaments of 20 countries, including Spain, have endorsed it.
European Commission president Jose Manuel Barroso welcomed the vote.
"The Spanish government and the parliamentary Houses have shown unwavering support for the European project and the successful ratification of the Treaty of Lisbon," he said in Brussels.