Redwell Wood is a 52.8-hectare (130-acre) biological Site of Special Scientific Interest near South Mimms in Hertfordshire. The local planning authority is split between Hertsmere Borough Council and Welwyn Hatfield District Council.

The site has ancient and secondary woodland, heath and scrub. The woodland canopy is dominated by pedunculate oak. Ground flora include bluebells and enchanter’s-nightshade, while heathland species include heather and the rare creeping willow.

There is access from Blackhorse Lane.

• List of Sites of Special Scientific Interest in Hertfordshire

51°42′29″N 0°14′45″W / 51.7081°N 0.2459°W / 51.7081; -0.2459