Gibside is an estate in Tyne and Wear, England. It is located in the valley of the River Derwent on the border with County Durham, between Rowlands Gill and Burnopfield. The estate is the surviving part of a Georgian landscaped park, primarily created under the ownership of Sir George Bowes (1701–60) and designed in large part by Stephen Switzer and William Joyce.

The park contains structures designed by James Paine, including a Palladian chapel; Daniel Garrett, including a banqueting house; and William Newton, but several are now ruined shells or have been demolished. Gibside Hall, the house at the centre of the estate, dates in part from the 17th century, is Grade II* listed, but is also a shell.

Gibside descended by marriage from the mid-13th century, and passed to the Bowes family in 1693. It was sold piecemeal during the 20th century; the banqueting house is now owned by the Landmark Trust, and much of the rest of the estate by the National Trust.

The Blakiston family acquired the estate by marriage in about 1540. Sir William Blakiston (1562–1641) replaced the old house with a spacious mansion between 1603 and 1620. Both the Royal (James I of England) coat of arms and the Blakiston coat of arms are seen over the entrance of the old Hall. The Gibside property came into the possession of the Bowes family in 1713; a result of the marriage in 1693 of Sir William's great-granddaughter, Elizabeth Blakiston, to Sir William Bowes (1657–1707) of Streatlam Castle, County Durham (now demolished).

Until 1722, the basis of the Bowes' influence was their own estate and house of Streatlam Castle. However, after that date the acquisition through marriage of the Blakiston estate of Gibside gave the Bowes family an even greater influence in the north of the county and a share in the immense wealth that was to be acquired from the coal trade. The Blakiston estate included some of the area's richest coal seams.

In 1767 the granddaughter of Sir William Bowes – the "Bowes heiress" Mary Eleanor Bowes – married John Lyon, 9th Earl of Strathmore and Kinghorne, who changed his surname to Bowes due to a provision in her father's will that any suitor had to take the family name. This was a device to continue the Bowes lineage in the absence of a male heir.

After the split inheritance dispute following the death of John Bowes, 10th Earl of Strathmore and Kinghorne, in 1820, it belonged to his legitimated son John Bowes until his death in 1885 (he is buried in the Gibside chapel), when under the entail it reverted to his cousin Claude Bowes-Lyon, 13th Earl of Strathmore and Kinghorne. It had been the main residence of John Bowes' mother, Mary Milner, by then Dowager Countess of Strathmore, and her second husband, the politician Sir William Hutt (who had been John Bowes' tutor), and remained in his ownership until his death in 1882.

Improvements to Gibside carried out by the Bowes-Lyon family in the 18th and early 19th centuries included landscaping, Gibside Chapel, built between 1760 and 1812, the Banqueting House, a column of Liberty, a substantial stable block, an avenue of oaks and several hundred acres of forest. The top floor of the main house was remodelled as a giant parapet in 1805.