Jason MacLean, 41, was wrestled to the ground and handcuffed by a Halifax police officer during the demonstration by health workers and other union members on Tuesday.
MacLean, who is the vice president of the Nova Scotia Government and General Employees Union, said in an interview that he was relieved by the police decision.
He said he works as a corrections officer at a provincial jail and was concerned that the incident could result in his suspension. He also was considering launching a complaint against the police, but will first meet with the officers involved and hear their explanation.
MacLean was among hundreds of health-care workers voicing their opposition to a controversial Liberal government bill that would reorganize bargaining units in the health sector.
He was taken away in a police van and a police spokesman said initially he would be charged with assaulting an officer.
At the time, police said the officer who made the arrest thought he saw the protester assault another officer.
But police now say after seeing a video of the arrest, they decided to drop the charge.
Police say the officer who made the arrest tried to arrange a meeting with the union member.
"The investigator reached out to the man who was arrested, however, he was unavailable to meet with police today," police said in a news release Thursday.
They said an investigator then called the man's lawyer to advise him no charges would be laid.
"While we would have liked to have met with the man in person to discuss the matter, we publicly apologize to him for the situation."
Note to readers: This is a corrected story. An earlier version of the story said the worker was 40 years old.