Picton Castle (Welsh: Castell Pictwn) is a medieval castle near Haverfordwest in the community of Uzmaston, Boulston and Slebech, Pembrokeshire, Wales. Originally built at the end of the 13th century by a Flemish knight, it later came into the hands of Sir John Wogan. The castle and gardens are now owned and managed by the Picton Castle Trust, a registered charity, for the benefit of the public. It is of unusual construction and has been remodelled several times during its history. The castle is a Grade I listed building and its gardens and park are designated at Grade II* on the Cadw/ICOMOS Register of Parks and Gardens of Special Historic Interest in Wales.