Attacks on nurses account for almost 90% of all hospital assaults.
There have been 279 assaults in HSE hospitals so far this year, and 249 (89%) were against nurses, new figures have revealed.
The statistics cover from the first day of 2019 until June 12, and were released to Sinn Fein Health spokeswoman Louise O'Reilly in a parliamentary question.
The figures do not include voluntary hospitals, private hospitals or other health services outside of HSE hospitals.
A leading nursing union has blamed the problems on under-staffing, overcrowding and under-capacity, which has plagued the health service for the last year.
They say that patients become frustrated at conditions and a minority unacceptably lash out at staff.
The union described the problems as creating a "pressure cooker environment".
Irish Nurses and Midwives Association general secretary, Phil Ni Sheaghdha, said: "Any assault on a frontline health worker is completely unacceptable. Nurses are clearly bearing the brunt of assaults - facing nearly 90% of attacks.
"But these figures are just the tip of the iceberg. Many more assaults go unreported, as nurses are often too busy to stop work and do the paperwork. The statistics also do not include voluntary hospitals, where problems are likely just as bad.
"Overcrowded, under-staffed services create a pressure cooker environment.
"That means frontline staff being put at risk for conditions they are not responsible for.
"With proper staffing, care would be faster and better, which would ensure tensions in hospitals don't build up."
Ms O'Reilly said the number of assaults "is staggeringly high".
"The safety of the excellent staff in our health service as they discharge their duties is paramount," the Sinn Fein TD said.
"Any assault or attempted assault on a member of the health service as they try to do their job is unacceptable.
"Nurses play a key role in the delivery of our public health services, and for them to face such high levels of assault is completely unacceptable.
"The HSE, and the Minister for Health, need to increase measures to reduce the number of assaults our nurses face.
"I urge the HSE to directly employ more security staff in emergency departments and throughout hospitals to ensure hospital employees are protected."
The health service has come under considerable criticism in the last year, with a number of strikes by nurses and hospital staff, ward closures and record-breaking overcrowding in hospitals across the country.
