Uroleucon sonchi is a species of aphid in the family Aphididae.

Known as the large sow-thistle aphid, it is a native of Europe, and has been introduced to several other countries.

[1][2][3][4] It principally feeds on the sow thistle (Sonchus sp.)

[5] U. sonchi is native to the Palaearctic region, but is now found in North and South America, the Middle East, Yemen, Africa, India, Japan, China, Korea, New Zealand, and (since 1995) Australia.

[6] This species feeds on many plants in the Asteraceae, mostly the tribe Lactuceae: sow-thistle (Sonchus oleraceus) and other Sonchus species, lettuce and other Lactuca species, endive, Emilia sonchifolia, Geropogon glabrum, and Picris hieracioides.