Three men were waiting inside the building when the 300-dealer Lincolnshire centre opened up at 9.45am on November 7.
Despite the shock of being confronted, and then grabbed, by the masked raiders, two female staff fought them off and managed to raise the alarm, and the would-be robbers fled via a window.
One of the women suffered minor injuries and bruising. Nothing was taken by the robbers.
Police believe they fled in a blue 4x4, driving away across the field at the back of the unit where Hemswell is based, and are appealing for anyone who may have seen suspicious activity in the area from the evening before, Tuesday, November 6, to get in touch.
Hemswell Antiques Centre owner Robert Miller said the staff were "very shocked" by the break-in.
"They were very brave in what they did," he told the Worksop Guardian. "Unfortunately this was a sign of the times. It was frightening for those involved but we will stand strong and won't let this happen again. Nothing was taken but we have got to catch these people."
Anyone with information should call Det Con Tina Kennedy of Gainsborough CID on 101, referring to incident 111 of November 7.