Lucile’s Creperie in Marmion Road was targeted between 5pm on Wednesday and 7.50am yesterday.
The front window was broken using an advertising board from a shop across the road. Glass was left strewn inside and outside the shop but nothing was stolen.
Owner Lucile Tourres said: ‘I feel so unlucky – it could have been anyone. I probably won’t be open until I can sort out the insurance out to replace the window.’
Lucile discovered the damage to her cafe when she arrived there yesterday to open. She called the police immediately.
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She added: ‘Nothing can be done. Even if I board up the window who would want to come in?
‘It would block the main window of the cafe.’
Marmion Road is home to many independent businesses and Lucile said the attack has come as a shock to the surrounding shop owners.
She hopes that looking through the CCTV footage of surrounding shops and from nearby Waitrose will shed some more light on who vandalised her cafe.
A spokesman for Hampshire police said: ‘We were called to reports of criminal damage at Lucile’s Creperie in Marmion Road.
‘A frame had been thrown through the front window.’
The business is one of the only creperies in the area and sells a range of French cheeses and other delicacies as well as traditional French upholstery.
Anyone with information should contact police on 101, quoting 44160358213.