The Royal National Hospital for Rheumatic Diseases increased its clinical research in the last year.
The hospital, known locally as the Min, has an international reputation for research, and carried out 22 clinical research studies in 2012/13, involving 710 patients.
This is an increase on the 434 patients who took part in 19 studies carried out in 2011/12.
Hospital research and development manager Jane Carter said: "It has always been a core principle of the Min to combine clinical research and development with high-quality patient care.
"We are delighted to have more than a 50 per cent increase in the number of patients taking part in research projects. Clinical research plays a critical role."
The hospital is keen to cement its reputation as a centre of excellence as it prepares to be taken over by the Royal United Hospital NHS Trust, and as patients are concerned to ensure it retains its world-renowned identity.
The city centre hospital has lost some of its NHS work as primary care trusts tighten their belts and look for treatment closer to home, and earlier this year shut a head injury unit.
The RNHRD clinical research projects currently under way include clinical trials into rheumatological conditions such as rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis and connective tissue diseases.
The trust also conducts research into fatigue management and chronic pain conditions including complex regional pain syndrome, for which two new trials will be beginning shortly.
Dr Jonathan Sheffield, chief executive of the National Institute for Health Research Clinical Research Network, said: "Patients always tell us how important it is for the NHS to take part in clinical research.
"I would like to congratulate the trusts in Bath for increasing the number of studies they do locally, and helping to bring research opportunities to patients."
