Blythswood Square is a square in the Blythswood Hill area of the City of Glasgow, United Kingdom. The square was built as a first part of a westward expansion of Glasgow upon the 470 acres of the Lands of Blythswood & Woodside stretching from the western side of Buchanan Street to the River Kelvin, near today`s University of Glasgow. These open grounds, mills and quarries were acquired by the Douglas-Campbell family in the 17th century. It is one of six squares in the city centre. 
The square is one of the residential developments on Blythswood Hill on the 35 acres of ground purchased in 1802 by William Harley, textile manufacturer and builder, from the Douglas-Campbells of Blythswood. His plan for the square and its adjacent streets was sketched out by architect James Gillespie Graham in 1819. The four Georgian terraces forming the square are Category A listed buildings and were completed in the 1820s by the trustees and successors of William Harley, and have facades designed by architect John Brash. From the 1920s the luxurious houses increasingly became offices and clubs including on the eastern side the Royal Scottish Automobile Club, which was elegantly restyled internally by architect James Miller in 1923. 
In 2009 the former RSAC building opened as the 5 star Blythswood Square Hotel. 
The Blythswood Square Proprietors association own and maintain the gardens in the central area. In summer months these are open at lunchtimes to the public and office workers in the neighbourhood.
- Glasgow Past and Present, by Senex and others, three volumes published in 1884
- Architecture of Glasgow by Andor Gomme and David Walker, published in 1968 and 1987
- Buildings of Glasgow by Elizabeth Williamson, Anne Riches and Malcolm Higgs, published in 1990