The first incident occurred at around 8.20 pm when a man armed with a knife entered a shop on the Ravenhill Road in south Belfast and threatened staff.
A sum of money was handed over and the man was seen to leave the shop and get into a silver car which was parked nearby on My Lady’s Road.
In the second incident, which was reported at around 11.25 pm, two males armed with knives, entered a fast food takeaway on the Cavehill Road in north Belfast and forced staff to open the till.
A sum of money was taken before the men fled the scene in the direction of Sunningdale Park.
One of the males was dark skinned and was wearing a black coloured hooded top.
The second male was white and was wearing a dark grey hooded top and was carrying a backpack.
There were no reports of any injuries to staff members following the incidents.
Detective Sergeant Keith Wilson would ask anyone who witnessed either incident or who has any information to contact detectives in Musgrave on 101 or Crimestoppers anonymously on 0800 555 111.