Ostallgäu is a district in Swabia, Bavaria, Germany. It is bounded by (from the west and clockwise) the districts of Oberallgäu, Unterallgäu, Augsburg, Landsberg, Weilheim-Schongau and Garmisch-Partenkirchen, and by the Austrian state of Tyrol. The city of Kaufbeuren is enclosed by but does not belong to the district.