Symmorphus allobrogus is a species of potter wasps belonging to the subfamily Eumeninae.

[1] Species within this genus are present in most of Europe, in the eastern Palearctic realm, and in the Near East.

They have a black thorax much longer than wide and a long and narrow abdomen with two yellow bands.

The main segment of the antennae of males are completely black.

Adult females prey on caterpillars and larvae of beetles (Chrysomelidae, Curculionidae) to lay eggs in them.