Guilleminot was recalled to active duty in 1805 and served as a topographical engineer in the Ulm and Austerlitz campaign. In 1808 he was sent to Spain and after the battle of Medina del Rio Seco he was promoted to "général de brigade". In 1809 he again served in Italy and the following year he again served in Spain. In 1812 he was part of the general staff for the Russian campaign. Promoted to "général de division", he was given command of XII Corps, which he led in the battle of Grossbeeren.