It follows a similar incident in Bolton Market at the weekend.
CCTV has been released showing a man walking out of Percival's newsagents in Prestwich holding the charity box.
A member of staff from the shop bravely chased after him but he managed to get away and police are now looking into it.
It follows a similar incident in Bolton at the weekend when a gang of three women used distraction tactics to steal several charity boxes including one for the British Legion from Bolton Market.
Jamie Bomsztyk owns a shops opposite Percival's and has set up a fund raising page to try and replace the money that has been taken
"It can be anywhere up to £300 in a box" Jamie told us
"Percival's is a busy shop so I'm sure it was quite full. It's disgusting, it's not only for members of the armed forces but for their families as well. It's a disgraceful act."
The fund raising page can be found here