Plessey was a British electronics company.
It can also refer to: Plessey Code, a British barcode system Plessey System 250, a computer system that implements capability based addressing Plessey railway station, a disused halt near Plessey village, in Northumberland Plessey Woods Country Park, near Plessey village, in Northumberland
See also Plessey v Ferguson Pleshey Plassey (disambiguation)