The owner of a jewellery store in Melbourne's south-east says staff are "fearing for their lives" after the second robbery at the shop in 18 months.

Jafari Jewellery in Malvern East was robbed for the second time on Monday morning, after it was a targeted during a brazen daylight robbery in May last year.

During that terrifying incident, the jewellery store owner hid in terror and nearby traders barricaded themselves inside as four masked men armed with crowbars and a hammer stormed the shop.

No charges have been laid over last year's incident.