The King's Theatre was commissioned by Howard & Wyndham Ltd under its chairman Baillie Michael Simons as a sister house to the company's Theatre Royal in Glasgow. Frank Matcham designed it, making the most of the prominent corner site with two decorative elevations in red Dumfriesshire sandstone, mixing Baroque and Art Nouveau influences. Built at a cost of more than £50,000, it opened on 12 September 1904. An iron canopy from the Saracen Foundry in Possilpark originally wrapped around the front, though it had gone by the Second World War.
In the 1930s the theatre broke with the custom of closing for the summer. In 1933 managing director A. Stewart Cruikshank tried out a late-starting variety bill called the Half Past Eight Show, first staged on 5 June that year. It changed weekly, drew enormous crowds and produced a record run of 31 weeks topped by Dave Willis. The King's also presented musical plays, drama, ballet and, before 1914, film seasons. Over the decades the stage was graced by performers including Sarah Bernhardt, Laurence Olivier, Katharine Hepburn, Tyrone Power and Ray Walston, and the Jackson Five and Dolly Parton appeared in a Royal Variety Performance in the late 1970s.
Pantomime arrived only in the 1960s, after the Alhambra Theatre closed, and quickly became the theatre's signature, with stars such as Stanley Baxter, Jimmy Logan, Rikki Fulton, Gerard Kelly and Elaine C. Smith. In 1967 Howard & Wyndham sold the building to Glasgow Corporation, securing its future at a time when many British theatres were closing. An extension was added to the rear in the early 1970s as part of the neighbouring Charing Cross Complex, and the theatre was designated a Category A listed building in December 1970.
The King's was a main venue when Glasgow became European City of Culture in 1990, and it underwent major refurbishment for the occasion. Management passed to the Ambassador Theatre Group in 2002 and the centenary was marked in 2004. A further interior restoration programme was announced in 2008 with Simpson & Brown as architects: the stalls and grand circle seating was replaced in autumn 2009 in a style in keeping with the building, with better legroom and no centre aisle in the stalls to improve sightlines, along with new carpet, a new orchestra pit railing and preparation for air conditioning.