Grey Southeast was a federal electoral district represented in the House of Commons of Canada from 1917 to 1935.

The southeast riding consisted of the towns of Durham and Hanover, and the villages of Markdale, Dundalk, Flesherton and Chatsworth, and the townships of Bentinck, Normandy, Glenelg, Egremont, Proton, Artemesia, Osprey, Holland and Sullivan.

In 1924, it was redefined to consist of the part of the county of Grey lying south of and including the townships of Sullivan, Holland, Artemesia and Osprey.

The electoral district was abolished in 1933 when it was redistributed between Grey North and Grey—Bruce ridings.

This riding has elected the following members of Parliament: