The officers are on a 30-day suspension with intent to dismiss, Ross said during a news conference on Thursday.
A total of 72 officers were placed on administrative leave after the investigation began back in June.
Four officers will be suspended for 30 days, while three will not face any discipline. The remaining officers will face disciplinary action ranging from reprimand to five-day suspension.
"I continue to be angered and very disappointed by these posts, many of these - in my view - violate the basic tenets of human decency," Ross said. "I'm saddened by the fact that there even some who would attempt to justify such hateful and vile behavior."
Commissioner Ross: It's disheartening that in 2019 we have people who have these views... I am very troubled and I understand the dismay that the public would have, because we have it as well. @PhillyPolice @6abc— Maggie Kent (@MaggieKent6abc) July 18, 2019
Ross said the posts contained such messages such as "death to Islam" or described African-Americans as "thugs." Some also suggested violence to transgender individuals.
According to Ross, the department considered several factors when deciding on discipline, including the officers' constitutional rights and the integrity of the police department.
Mayor says he is deeply disturbed as Philadelphia Police department is looking into racist and offensive comments that appeared on several officers' Facebook pages. @6abc— Gray Hall (@GrayHall6abc) July 18, 2019
In a statement, Fraternal Order of Police Lodge #5 President John McNesby said the FOP is "disappointed that our officers will be terminated without due process."
The FOP is meeting with each officer to prepare a response.
"FOP Lodge #5 and our members condemn racist and hateful speech in any form," said McNesby. "The overwhelming majority of our members serve this city with integrity and professionalism."
The department has been investigating the posts since last month. The posts were compiled in a database by the Plain View Project and published by Injustice Watch, a not-for-profit journalism organization.
Attorney Emily Baker-White reviewed public posts of more than 14,000 officers in eight cities, including Philadelphia, York (Pa.), Dallas, St. Louis and Phoenix.
According to Injustice Watch, of the more than 1,000 Philadelphia officers identified on Facebook by Baker-White, 328 of them posted troubling content. According to the research some of the entries were made as far back as 2010.
Many of the comments called for violence against Muslims, protestors, immigrants, and those accused of crimes. Some posts celebrated police brutality and in a few cases called for violence against women.
The city hired an independent law firm to help investigate the posts.
The commissioner said all officers will have to take part in anti-racist and anti-bias training. He said social media accounts will be monitored, in hopes of preventing another black eye to the department like this one.
"I just say to the public that we will work. You have our commitment we will work tirelessly to make this situation better. We know it will take a tremendous amount of effort on our part," said Commissioner Ross.
So far the names of the officers have not been revealed. Commissioner Ross said none of the officers on leave denied making the posts.