A 47-run victory over Namibia ensured Afghanistan will compete in their second consecutive World Twenty20 tournament.
After making their one-day international debuts against Pakistan recently, Afghanistan were disappointed to be excluded from the Asia Cup currently being held in Bangladesh.
However after their success in Dubai there will be no denying the team their place in the 20-over global showpiece, to be held in Sri Lanka later this year.
"It's really a big day for us," said Afghanistan captain Nawroz Mangal.
"Coming to this tournament as defending champion, it put a little pressure on the team, especially in the shorter format of 20 overs where it's anybody's game.
"The boys did well and they proved they are deserving winners, and a deserving team to go to the World Cup."
Afghanistan lost both games in the 2010 tournament, against India and Australia, and coach Kabir Khan is aware of the challenge facing his team in Sri Lanka.
He said: "We want to have a good tournament and give full and tough matches to the opposition. If we win one or two, I don't mind. But if we lose, we want to lose giving 100 per cent."