The siege of Šabac or Szabács occurred on 7 July in the year 1521 when the Ottoman Empire conquered the Šabac fortress.

The Ottomans under the leadership of Ahmed Pasha conquered the fortress of Šabac on 7 July in 1521.

[1] After its conquest Suleiman said that it was one of the cities he had conquered and that it must be improved.

[1] He ordered towers to be built around the fortress and a moat around it filled with water from Sava.

[1] Suleiman spent 10 full days on the Sava at Šabac overseeing the construction of the pontoon bridge.