The Middlesex Quarter Sessions was the quarter session court for the county of Middlesex, England. Membership was made up of the justices of the peace. The quarter sessions heard criminal cases and also had a role in the civil administration of the county. Administrative functions of the quarter sessions lasted from the 16th century to 1889 and included taxation, licensing, prisons, asylums and bridges. The Middlesex sessions area was reduced in 1889.