Campaigners are fighting to reopen 12 beds at Rothbury Community Hospital.
Protesters, many carrying placards, marched from the Haugh car park to the hospital.
Berwick MP Anne-Marie Trevelyan was among those who attended.
She tweeted afterwards: ‘Excellent turnout for our @SaveRothburyCH rally in #Rothbury this morning despite the rain!’
The future of the inpatient ward is in the hands of Health Secretary Jeremy Hunt, after Northumberland County Council’s health and wellbeing overview and scrutiny committee referred the matter to him in October.
A month previously, the joint executive board of the Northumberland Clinical Commissioning Group (CCG) voted unanimously in favour of permanently closing the facility and shaping the existing services around a Health and Wellbeing Centre at the hospital.
The beds were shut in September 2016 – at first temporarily – due to low usage, according to the NHS.
The closure sparked dismay in the community and a campaign to reopen the beds has been running ever since.
The local demonstration coincides with the NHS Day of Action in Newcastle.