The Southern Greater Poland dialect (Polish: gwary południowowielkopolskie) belongs to the Greater Poland dialect group and is located in the part of Poland. It borders the Northern Greater Poland dialect to the north, the Eastern Greater Poland dialect to the northeast, and the new mixed dialects to the south.

As in other Greater Polish dialects, voicing of word-final consonants before vowels and liquids is present here. Also typical of Greater Polish dialects, mazuration is not present.

-y often diphtongizes to -yj, as in many Greater Polish subdialects, typically word-finally in the south but sometimes also word-medially in the west. A few instances of i after a soft consonant have shifted to y (and softness is retained): we chliywie; kuknyliy; mówiliy. Final -aj shifts to -ej.

Slanted é raises to y. Slanted ó raises to u. Slanted á raises to o.

Regionally, Word-medial -ę- denasalizes and raises: czyść (część). ę word-finally denasalizes to -e, and word-medially as well, except when before a sibilant, where some nasality is retained: bede (będę), but czyⁿś (część). ą word-finally is typically realized as -om, -óm. Nasal consonants can cause raising of e to generally y, but sometimes o or i. The ending -nąć and its inflections can shift to -nóć or sometimes -nóńć.

o labializes to ô not only word-initially, but also sometimes word-medially or word-finally.

n, d, t can palatalize when near e, i, y (notably after these vowels, when typically they need to be before them): malinia (malina), but palatalization after y is rare: pierzynia||pierzyna.. ł is often lost, especially intervocalically: syszaam (słyszałam). kt shifts to cht. trz is simplified to cz. Some consonants assimilate in softness: dźwi (drzwi); przyjśli (przyszli). Sometimes j is inserted before palatal consonants: zajś (zaś). Final m is sporadically lost: poty (potem).

Many uncontracted forms are retained, usually amongst older speakers: grajesz (grasz).