Sometime between 8pm on Sunday (20 February) and 1.40am Monday (21 February), unknown person/s broke into the antique shop on Military Road, Mosman.
Most of the items stolen were solid silver with an English or Russian origin. There was also a large amount of ivory and porcelain of Chinese and French origin taken.
The stolen items are valued at approximately $300,000.
Police from Harbourside Local Area Command are appealing to the public and antique dealers for information relating to the theft.
Police have released a number of images of some of the stolen items, including that of jewellery, vases and a tea set.
Anyone with information should contact Crime Stoppers on 1800 333 000.