This year's festival will be the biggest, with two new outdoor stages in Liverpool and, for the first time, one in Birkenhead.
Altogether, 150 bands from 20 countries will take part.
In addition to the six outdoor stages, there will be 40 indoor venues.
The crowd at the Pier Head alone is likely to exceed 20,000.
The programme is expected to attract a total audience of 300,000.
Cllr Warren Bradley, Liverpool's executive member for culture, said: "The Mathew Street Festival is moving on to a new level catering for all ages and tastes."