Campbell's comfortable victory in a personal best of 22.05 seconds was Jamaica's first gold of the Athens Games and the first sprint gold by a Jamaican athlete since Don Quarrie won the 1976 men's 200 metres.
Three Jamaicans made the women's 100 final -- Campbell, Aleen Bailey and Sherone Simpson. Bailey finished fourth in the 200 too and Campbell expects them to win the relay, where defending champions the Bahamas and the United States will be their main rivals.
"All the ladies are very motivated," the 22-year-old Campbell told her post-race news conference. "We have a group of ladies who have a lot of confidence.
"We had three in the 100 final. We are confident and everyone is thinking of the gold. As long as we run a perfect relay and get the baton round
In Wednesday's 200 Campbell burned out of the blocks and produced a superb bend, the key to her victory over American 18-year-old Allyson Felix and Debbie Ferguson of the Bahamas, second and third respectively.
"I executed that curve, I really ran it well," Campbell said. "I knew Allyson would get tired after about 150. I didn't think she would catch me. I had the race won when I cleared the curve first."
Felix's time of 22.18 was a world junior record and she was delighted to have won her first Olympic medal. "I had a great Olympic experience and I am very pleased with it. This is just a starting point for me," she said.
Ferguson's bronze followed the gold won by compatriot Tonique Williams-Darling in the 400 metres on Tuesday.
"I think per capita the Bahamas actually won the Olympics," the 28-year-old Ferguson grinned.