Mayor Jerramiah Healy announced Thursday that the Police Officers Benevolent Association approved the agreement Wednesday night by a vote of 341 to 164.
The layoffs were to take place Feb. 15. Officials blamed the city's financial woes. Jersey City has 830 police officers.
The agreement must be approved by the city council.
Several cities in New Jersey have laid off police in recent months. More than 150 officers in Newark lost their jobs in November, and Atlantic City let 60 officers go before hiring 17 back. This month, Camden laid off nearly half of its police force in a cost-cutting move.