Cornwall Partnership Trust was caring for 10 coronavirus patients in hospital as of Tuesday, figures show.
NHS England data shows no people were being treated in hospital for Covid-19 at 8am on September 21.
There were three beds occupied by Covid-19 patients four weeks ago in Cornwall Partnership NHS Foundation Trust.
Across England there were 7,024 people in hospital with Covid as of September 28, with 160 of them in mechanical ventilation beds.
The number of Covid-19 patients hospitalised nationally has increased by 24% in the last four weeks, while the number on mechanical ventilators has increased by 11%.
The figures also show that 14 new Covid patients were admitted to hospital in Cornwall Partnership NHS Foundation Trust in the week to September 26. This was up from two in the previous seven days.