Up against a truly world-class field, the 20-year-old from Alloa, who already had three bronze medals from this meet, produced his trademark strong finish to get the touch ahead of Olympic champion Kyle Chalmers of Australia and South African superstar Chad le Clos, who took joint silver,
In the blue riband event of the swimming programme, Scott was viewed as a genuine medal chance but chased down the big boys and scored a stunning win in 48.02 seconds.
The gold added to the bronzes Scott had already won in the 200m freestyle, 4x100m freestyle relay and 200m butterfly.
Scott then made it a record five medals from the Gold Coast - after also being part of Scotland’s bronze medal winning 4x200m freestyle relay.
But it was the men’s 100 metres freestyle title a significant and stunning triumph.
In a stellar field, the University of Stirling swimmer finished strongly to touch the wall in 48.02 seconds, overhauling South Africa’s Le Clos, who tied with Australia’s Chalmers.
“It didn’t matter who you put in that pool, I’m Commonwealth champion,” said Scott, who has overtaken fellow swimmer Gregor Tait’s Scottish record of four medals from a single Commonwealth Games.
England’s Siobhan O’Connor was dominant in winning the women’s 200m individual medley.
After claiming six medals at Glasgow 2014, including 200m individual medley gold, O’Connor streamlined her programme here and seized her one individual opportunity.
The 22-year-old Bath swimmer finished in 2mins 09.80secs, while England’s Aimee Willmott, the 400m individual medley gold medallist, was fourth. Scotland’s Hannah Miley finished sixth.
O’Connor said: “I felt a great deal of nerves coming into it. Four years ago I was the underdog and it was a massive shock to win.
“Four years on it’s a bit different. I just really wanted to try to get my confidence back again.
“I’m really, really happy with that swim and really pleased to win this.”
Australia’s dominance of the pool programme continued, with five gold medals from eight events on day four, including in the concluding men’s 4x200m freestyle relay.
James Guy was on the anchor leg for England and overtook Scotland to secure silver.
Guy combined with Cameron Kurle, Nick Grainger and Jarvis Parkinson, while Scott was joined by Stephen Milne, Dan Wallace and Mark Szaranek in the Scotland quartet.
Adam Peaty advanced to the men’s 50m breaststroke final in a Games record of 26.49.
The 23-year-old defended his 100m title on Saturday, completing a four-year unbeaten sequence in the event, and is seeking to win a first Commonwealth 50m title.