No one was injured during the incident which occurred at the Ladbrokes betting office at St Francis Terrace in the Collon area of Pennyburn shortly before 7.00pm.
The shots were fired by a man whose faced was masked with a hood and scarf and who demanded money from a member of staff.
A PSNI spokesperson asked anyone who was in the area last night and could help police with their enquiries to contact CID on 0845 600 8000.
Alternatively, if someone would prefer to provide information without giving their details, they could contact the independent charity Crimestoppers and speak to them anonymously on 0800 555 111.
It is the second betting office to be targeted by robbers in the city within a 48 hour period.
Shortly before 9.30pm on Saturday, a man got away with a sum of cash after holding up staff at a betting office on Racecourse Road in the Shantallow area.
The robber was described as being in his 20’s, approximately 5’10” tall, of slim build and wearing a dark grey coloured hooded top, dark coloured track bottoms, gloves and a hat and scarf covering his face.
Following that incident, Sinn Fein Councillor Tony Hassan urged business owners not to keep large sums on money on their premises in the run-up to Christmas.