The pagers, which have been funded by Sheffield Children's Hospital Charity, have been introduced to allow parents to roam up to a mile away if clinics are late or doctors are called to an emergency.
The Children's Hospital is one of the first in Britain to begin using the state-of-the-art patient paging systems in a bid to help reduce the stress of waiting times.
Bleepers are handed out by reception staff and buzz five minutes before the family are needed for their appointment, giving them time to get back.
The director of nursing and clinical operations at Sheffield Children's Hospital NHS Foundation Trust, John Reid, said: "The pagers are a great addition to our outpatient department and we're delighted to be able to give parents the chance to free up some of their time.
"It's important to us that families get a good balance between excellent medical care and providing a good overall experience at our hospital. Sometimes all mums and dads want is a short walk without the fear of missing their slot.
"We're very grateful to the charity for funding these extra innovative pieces of equipment which really make a big difference to families."
More pagers will be introduced in other departments later this year and will also be issued to parents whose children are undergoing surgery.
David Vernon-Edwards, director of the Children's Hospital Charity, said: "These bleepers are an excellent idea. They really make a difference for families as it can be difficult entertaining a child in a small space if there is a wait.
"This way they can go to the cafe or into Weston Park and feel their time is being better spent than just sitting on a corridor."