John Spencer won his third World Snooker Championship title by defeating Cliff Thorburn by 25 frames to 21 in the final.

Qualifying matches took place from 28 March to 7 April 1977 at Hounslow Civic Centre and Fisher's Snooker Centre, Acton, to select eight qualifiers to play against the eight top-seeded players from the 1976/1977 snooker world rankings in the main tournament.

Ray Reardon, who had won the annual championship each year from 1973 to 1976, was defeated 6–13 by Spencer in the quarter-finals.

British Army soldiers stationed in India invented snooker, a cue sport, in the late 19th century.

[1] Joe Davis won the first World Snooker Championship, which the Billiards Association and Control Council (BA&CC) organised in 1927.

[2]: 23 [3] In the "modern" era of the sport, which started in 1969 when the World Championship reverted to a knockout format,[4] snooker has become increasingly popular worldwide, especially in East and Southeast Asian nations such as China, Hong Kong and Thailand.

[9] Ray Reardon was the defending champion, having defeated Alex Higgins 27–16 in the final of the 1976 World Snooker Championship[10] The top-eight players in the 1976/1977 snooker world rankings were exempted to the main tournament, where they each faced a player from a qualifying competition.

[10][15][16] Watterson booked the venue at a cost of £6,600, and made personal financial guarantees for the championship before Embassy's sponsorship had been secured.

[19][20][21] The breakdown of prize money for 1977 was:[22] The WPBSA first published official world rankings for players on the main tour for the 1976–77 season.

Willie Thorne won six consecutive frames to complete an 11–6 defeat of Bernard Bennett.

Jim Meadowcroft gained a 6–3 lead against Patsy Fagan but lost 9–11 after the pair had been level at 8–8.

Maurice Parkin withdrew from the tournament due to illness, giving John Pulman a win by default.

[11][27] Fagan, Virgo, Mountjoy and Thorne qualified to make their World Championship debuts.

Dennis Taylor concluded a 13–11 win against Perrie Mans with a break of 76, the highest of their match, in the 24th frame.

The Snooker Scene match-report assessment said: "Even when the title was slipping away from [Reardon] he never seemed able to focus his concentration and stop making mistakes".

At the start of the third session, Thorburn made a 100 break, which included a cocked-hat double on the final red ball, and led 12–9 at the close of the penultimate day.

[29] During the fourth session, Thorburn gained a 13–11 advantage[39] and extended it to 15–11 but Spencer won the next four frames to make it 15–15.

His previous cue was smashed in a car accident just before the 1974 Norwich Union Open; despite repairs, Spencer was not confident about using it so he purchased a new, two-piece implement whilst on tour in Canada.

Having made several century breaks with the new cue following his return to England, Spencer decided to use it for the championship only two months before the tournament.

[11][40] Snooker historian Clive Everton wrote Spencer "exploded two myths" by winning with a two-piece cue, a type of implement that was generally seen as suitable for pool but not snooker, and having only used it for two months, when most professional players thought it took many months to become proficient with a new cue.