The Ketelmeer is the tongue of the IJsselmeer into which the River IJssel drains, it is situated between the polders Noordoostpolder (North-east Polder) and Oostelijk Flevoland (East Flevoland), and connects the river IJssel to the IJsselmeer.

It is one of the bordering lakes, a continuous body of water which separate Flevoland from the Noordostpolder and the ancient lands of the provinces of Gelderland and Utrecht.

It is via Ketelmeer that the IJsselmeer connects to the Zwarte Meer and the Veluwemeer, the strip of water which separates Flevoland from the coast of the mainland.

The Ketelmeer borders two buurtschappen, on the opposite sides of the lake: Ketelhaven on the south and Schokkerhaven on the north, both located roughly halfway the lake, though Ketelhaven is still located about one kilometer further to the east.

The Ketelbrug is a bascule bridge over the Ketelmeer connecting the Noordoostpolder and Oostelijk Flevoland.