The 1978 Open Championship was the 107th Open Championship, held 12–15 July over the Old Course at St Andrews, Fife, Scotland. Jack Nicklaus won his third and final Open championship, two strokes ahead of runners-up Ben Crenshaw, Raymond Floyd, Tom Kite, and Simon Owen. It was the fifteenth of his eighteen major championships and marked the completion of his third career grand slam. Defending champion Tom Watson was a co-leader after 54 holes, but four consecutive bogeys on the front nine led to a 76 (+4). Watson finished six strokes back in a tie for fourteenth place.

Course

Previous lengths of the course for The Open Championship (since 1950):

Round summaries

First round

Wednesday, 12 July 1978 Source:

Second round

Thursday, 13 July 1978 Source:

Third round

Friday, 14 July 1978 Source: Amateurs: Miller (+2), Brodie (+4), McEvoy (+5), Godwin (+6).

Final round

Saturday, 15 July 1978 Amateurs: McEvoy (+5), Miller (+6), Brodie (+7), Godwin (+10). Source: