Some 51 nurses have been suspended for taking part in an illegal strike.
The nurses have been on strike since March, citing a heavy workload and threats by the community following the disappearance of twin babies.
Health executive Benard Muia said the county public service board is interviewing more than 1,500 applicants.
Speaking at the hospital on Monday, Muia said the county will hire 100 nurses, 30 of them to be posted to other health facilities.
“We have given Pumwani preference because of its recent challenges,” he said.
The country’s largest maternity hospital receives between 70 and 80 patients a day with only three to five nurses attending to them now.
“The challenges that Pumwani and other hospitals in the city have gone through should never happen again. We will hire as many nurses as required,” said Health Chief Officer Robert Ayisi.