Sir Walter Calverley-Blackett, 2nd Baronet (18 December 1707 – 14 February 1777) was a British baronet and politician who sat in the House of Commons from 1734 to 1777.
He was born Walter Calverley at Otley, the only son of Sir Walter Calverley, 1st Baronet, and Julia Blackett, daughter of Sir William Blackett (1657-1705), 1st Baronet. He entered Balliol College, Oxford, aged 16 on 28 February 1724. In 1728, he inherited the substantial estates of his uncle Sir William Blackett, 2nd Baronet, at Cambo and Allendale, Northumberland, on condition that he married Elizabeth Orde (his uncle's natural daughter) within twelve months and adopted the name and coat of arms of Blackett. The marriage took place on 29 September 1729 at Newcastle. His change of surname to Blackett was later confirmed by an Act of Parliament in 1733.
He was High Sheriff of Northumberland in 1731–32 and elected Tory Member of Parliament in the British House of Commons for Newcastle-upon-Tyne over seven parliaments from 1734 until his death. He was an Alderman of the City of Newcastle and Mayor five times, in 1735, 1748, 1756, 1764 and 1771.
He inherited Sir William Blackett's mansion at Pilgrim Street, Newcastle and in 1749 inherited his father's baronetcy and estates at Calverley and Esholt, Yorkshire, which he soon sold. He settled at Cambo, where he expended considerable sums on the improvement of Wallington Hall, remodelling in the then fashionable Palladian style to designs by architect Daniel Garrett. In 1755, he commissioned Garrett to build a folly in the style of a medieval castle (Rothley Castle) on the hillside above Wallington.