The catch is the first charity fish to be caught as part of the Territory's Million Dollar Fish tourism campaign.

"I've been fishing in the Territory for over five years and never thought I would reel in a tagged fish," he said.

"I've never won anything in my life, I must admit it's a pretty good feeling."

Mr Waye said he caught the fish on February 4, at Bridge Lagoon, about 20 km from where the fish was originally tagged and released at Hardies Lagoon.

Worth $5,000 in total, the purple tagged fish will see $2,500 go to Mr Waye, and $2,500 donated to Darwin Star Ball, which raises money for the Starlight Children's Foundation in the Top End.

"My mate and I were pretty excited when we saw the purple tag - we knew what it was straight away," Mr Waye said.

"My mate and I are going to go halves in the money - I've already got plenty of fishing gear, so will probably put the cash towards vehicle registrations.

"The Starlight Children's Foundation has been doing amazing things for years, so it makes me feel good to be able to donate money to help the kids."

At the beginning of the fifth season of the competition, 121 barramundi were tagged and released across the Territory.

Of those, 100 carried $10,000 prize tags, 20 carried purple charity tags, and one was marked with the lucrative red, million dollar tag.

However, with zero of the million dollar fish caught in the competition yet, they are all in play.

"Fishing is a way of life for many Territorians, and I would like to congratulate local man Adam Waye on catching the first charity fish," the Northern Territory Major Events Company general manager Tim Watsford said.

"I would urge anglers from right across the country to come to the Territory and try their luck at reeling in the $1 million fish."

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