People are being urged not to avoid going because of the coronavirus pandemic.
According to Oxford University Hospitals - the trust which runs the John Radcliffe and the Horton General in Banbury - attendance last month was "significantly lower than previous years"
Staff are encouraging people to still attend their Emergency Departments, if they need to.
They're concerned that people are putting their health at risk by not going to hospital to avoid overburdening services during the outbreak.
The Trust says Emergency Departments are still available to those who need urgent medical care.
Sachin Mandalia, Clinical Lead for the Emergency Department at the John Radcliffe Hospital, said: "We want to remind people of the importance of seeking help if you are unwell.
"We're worried that really sick or injured people may be avoiding coming to hospital for fear of being a burden on our services during the COVID-19 pandemic, but this really isn't the case.
"Our staff are here for you, and will treat any serious conditions or ailments you may have.
"We have systems in place to triage patients with suspected COVID-19, so everyone who comes to our hospitals will be treated in a safe manner."
National advice for people who think they may have COVID-19 remains to visit NHS 111 online and self-isolate for seven days.