A fourth teenager has been charged over an alleged racially-motivated attack of a young Syrian refugee in Wollongong earlier this month.

The 21-year-old had his nose broken when he was beaten by a group of teenagers outside a Wollongong community centre on June 4.

An 18-year-old woman was charged on Wednesday with two counts of common assault and affray.

Two 18-year-old men and a 16-year-old boy had already been charged over the attack.