Cheltenham took the lead thanks to Martin Devaney, though the lead was only to last 14 seconds before Paul Hall equalised for the Diamonds.
Donkey arsed Julian Alsop restored the lead for the Robins, whilst John Finnigan sealed the win for Cheltenham with ten minutes to go.
The victory for Town continues a remarkable run of results, out of eleven finals played there the winning sides have always used the `lucky` north dressing room.
Robins manager Steve Cotterill was understandably pleased with the day.
"I always said this is the way to go up," he said.
"Cheltenham will never have another season like this - getting to the fifth round of the FA Cup, the play-off final - and I was just pleased we managed to have the lucky dressing room."
Elsewhere the Doncaster Belles were beaten in the women's FA Cup final this afternoon, losing 2-1 to Fulham ladies, the first professional women's team in Europe.
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