Research by the TUC showed that one in 13 BAME employees are in insecure jobs, compared with one in 20 white employees.
Black workers in particular face insecurity at work, and are more than twice as likely as white workers to be in temporary and zero-hours work, said the union organisation.
Its report revealed that between 2011 and 2016, the number of black workers on temporary contracts rose by 58%, over seven times the increase for white workers.
Black women have been the worst affected, with 82% more now in temporary jobs than in 2011.
TUC general secretary Frances O’Grady said: “This problem isn’t simply going to disappear. Dealing with insecure work has to be top of the list for the next government.”