Itzstedt is an Amt ("collective municipality") in the districts of Segeberg and Stormarn, in Schleswig-Holstein, Germany.

The seat of the Amt is in Itzstedt.

It is one of the two Ämter (with Großer Plöner See) in Germany that joins municipalities into two different districts, but only Tangstedt is located in Stormarn.

The Amt Itzstedt consists of the following municipalities: