List of Sites of Special Scientific Interest in Mid & South Glamorgan

This is a list of the Sites of Special Scientific Interest (SSSIs) in the Mid and South Glamorgan Area of Search. For SSSIs elsewhere in Wales, see List of SSSIs by Area of Search.

* Aberbargoed Grasslands
* Barry Island
* Blackmill Woodlands
* Blaenrhondda Road Cutting
* Brofiscin Quarry, Groes Faen
* Bryn - Bach, Cefn Cribwr
* Bryncarnau Grasslands, Llwydcoed
* Brynna a Wern Tarw
* Caeau Cefn Cribwr
* Castell Coch Woodlands and Road Section
* Cefn y Brithdir
* Clemenstone Meadows, Wick
* Cliff Wood - Golden Stairs
* Cnap Twt
* Coed y Bedw
* Coed y Bwl
* Coedymwstwr Woodlands
* Cog Moors
* Cors Bryn-y-Gaer
* Cosmeston Lakes Country Park
* Craig Pont Rhondda
* Craig-y-Llyn
* Cwm Cadlan
* Cwm Caner Mawr
* Cwm Cydfin, Leckwith
* Cwm Cyffog
* Cwm Du Woodlands
* Cwm Glo
* Cwm Risca Meadow
* Cwm Taf Fechan Woodlands
* Cynffig/Kenfig
* Daren Fach
* Daren y Dimbath
* East Aberthaw Coast
* Ely Valley
* Ewenny and Pant Quarries
* Fforestganol a Chwm Nofydd
* Flat Holm
* Garth Wood
* Glamorgan Canal / Long Wood
* Hayes Point to Bendrick Rock
* Lisvane Reservoir
* Llanbradach Quarry
* Llanishen and Lisvane Reservoir Embankments
* Llantrisant Common and Pastures
* Lower House Stream Section
* Merthyr Mawr
* Monknash Coast
* Mynydd Ty-Isaf, Rhondda
* Nant Gelliwion Woodland
* Nant Glais Caves
* Nant Whitton Woodlands
* Nash Lighthouse Meadow
* Nelson Bog
* Old Castle Down
* Penarth Coast
* Penmoelallt
* Penylan Quarry
* Pysgodlyn Mawr
* Rhymney River Section
* Rumney Quarry
* Southerndown Coast
* Stormy Down
* Sully Island
* Ty Du Moor
* Waun Cimla
* Waun-fawr, Cefn Cribwr
* Wern Ddu Claypits
* Woodland Park and Pontpren