The Stand up to Racism (SUTR) event saw crowds gather in the city’s George Square before a march through the streets.
A minute’s silence was also held at 11am to remember those killed in the New Zealand terror attacks.
A statement from Unite the Union Scotland said: “All of us who campaign and work for a world free from fear, hatred and bigotry must redouble our efforts.
“The current political climate has created an environment where racism has once again reared its ugly head.”
It continued: “There has been a rise in far-right, racist and xenophobic attitudes which has been given oxygen by some of the current debates surrounding the decision by the British public to leave the European Union.
“There is an urgent need for all decent-thinking people to come together under a banner of democracy and equality to stand against those that try to divide us.
“The message is clear; let’s stand together to promote tolerance, acceptance and equality. Unite pledges to play our full part.”
Some of the crowd chanted “we stand with Christchurch” as they entered the square.
A number of SUTR rallies were held around the UK.
There was a heavy police presence as the Glasgow event got under way.
A petition, backed by Glasgow Fight Racism Fight Imperialism (FRFI) and Glasgow Palestine Human Rights Campaign, had been launched online ahead of the rally to try and prevent the Confederation of Friends of Israel in Scotland (COFIS) and Glasgow Friends of Israel (GFI) attending.
A number of counter-protesters were kept at the other side of George Square, away from the main rally.