The numbers were released as social media sites announced they would clamp down on the sharing of self-harm images.
Public Health England figures show that 1,538 emergency admissions to hospitals in Nottinghamshire in 2017-18 were for intentional self-harm injuries.
It means that 197 cases were registered for every 100,000 people in the area – the same rate as the average across the East Midlands.
Most of the cases concerned female patients, with 964 admissions of women or girls for self-harm, 63% of the total number.
Recently, photo-sharing platform Instagram announced that it would be banning graphic images of self-harm on its site.
The social network’s head Adam Mosseri said the firm recognised it “needs to do more to protect the most vulnerable in our community”.
Across England, the number of self-harm cases has gradually declined since 2013-14. Last year, there were 185 admissions for every 100,000 people.
Stephen Buckley, from mental health charity Mind, said the decline in emergency admissions may not tell the whole story.
He said: “While the data shows a reduction in the number of people being given emergency treatment after self-harm, it doesn’t explain why this might be the case.
"Reasons for this might be that people are getting help in different ways when in crisis, or perhaps that a previous poor experience of treatment at A&E has discouraged them from returning.
"There are alternatives to A&E, such as crisis houses, but it’s vital to seek emergency care when needed – and equally vital that A&Es provide effective support.
"It’s also important to remember that the data doesn’t show how many people are self-harming but not receiving any treatment or help at all."
The PHE figures also include information on other factors related to mental health in Nottinghamshire.
They show that depression is as common among adults as the average across England. Last year, 10% of patients registered with doctors reported the condition.
Suicide rates in Nottinghamshire are relatively low. Between 2015 and 2017, 168 people took their own lives, at a rate of eight per 100,000.
The average across England was 10 per 100,000.
The Samaritans operate a round-the-clock freephone service 365 days a year for people who want to talk in confidence. They can be contacted by phone on 116 123 or by visiting samaritans.org.
A spokesman for Nottinghamshire Healthcare NHS Trust, said: "We work closely with our acute hospital colleagues to ensure appropriate and timely care is given to patients who present at emergency departments with a mental health issue. Our Rapid Response Liaison Psychiatry Service operates within both King’s Mill and QMC hospitals. It provides specialist assessments for patients attending emergency departments as the result of possible mental health issues.