In 1870 von Fransecky became the commanding general of the Prussian 2nd Corps. During the Franco-Prussian War the Prussian 2nd Corps was part of the German 2nd army commanded by Prince Friedrich Karl. Fransecky distinguished himself at Gravelotte, where he reached the battlefield after a 16-hour forced march. After Gravelotte, 2nd Corps was part of the troops besieging Metz. After the fall of Metz Fransecky and 2nd Corps were sent to Paris. During the Siege of Paris Fransecky was given command of the troops between Seine and Marne. On 2 December 1870 Ducrot tried to break through the German ring at Villiers but the sortie was stopped by troops under Fransecky.