Kirkby Fleetham is a village in the Hambleton district of North Yorkshire, England about east of the A1 road. Along with the two nearby villages of Great Fencote and Little Fencote it forms the civil parish of Kirkby Feetham and Fencote. It has a population of 560.
There were two distinct villages named Kirkby and Fleetham at one time. Both are mentioned in the Domesday Book as Cherchebi and Fleetha both belonging to the lands of Count Alan of Brittany. The nearby hamlets of Gt and Lt Fencote are referred to in the Fleetham entry as the Fencotes. The lands of Fleetham before the Norman Conquest were owned by Gamli, son of Karli and Uhtred. After 1086 the manor was granted to Odo the chamberlain. The lands around Kirkby remained with Aldred (Eldred) throughout that time period. The name derives from a combination of kirkju-býr, Old Norse for village with a church, flēot the Old English for small stream and hām the Old English for farm.
The manor of Kirkby was passed to Aldred's son Gospatric, whose daughter Godareda succeeded to his lands, but a clear line if succession does not emerge again until William Giffard in the thirteenth century, whose demesne lordship subsequently lapsed. The demesne titles were then in the possession of the Stapleton family until 1514 when Sir Thomas Metham let the lands to the Conyers. The heirs of the Methen family sold the manor in 1600 to Leonard Smelt. On the death in 1740 of Leonard Smelt, the M.P. for Northallerton, the manor passed to the Aislabie family who, via the distaff side, held it until 1845. At the turn of the twentieth century it passed to the Courage family.
The manor of Fleetham passed to the Scrope family of Castle Bolton in the thirteenth century. It was passed down that line of descent via Lord Fauconberg and the Darcy family until 1670 when it was conveyed to Richard Smelt, younger brother of the then lord of Kirkby, thus uniting the two manors.
The moated site in the parish at , south of the Three Tuns Inn, is a scheduled ancient monument. It is the site of moated manor house, built in about 1314, on the site of an earlier motte and bailey castle.