Maros-Torda was an administrative county (comitatus) of the Kingdom of Hungary.

Its territory is now in central Romania (eastern Transylvania) and has been administratively succeeded by county Mureș which consist of about half the territory of the previous Maros-Torda administrative county.

Its county seat was Marosvásárhely (present-day Târgu Mureș).

In 1920, after the Treaty of Trianon, the county became part of Romania, except after the Second Vienna Award, between 1940 until the end of World War II, when much of the county's territory was awarded to Hungary.

Today, its territory lies in the present (larger) Romanian county Mureș.