The two senior members of staff in the university's marketing and student recruitment department were dismissed last December.
They had previously expressed concerns at plans to restructure the department.
The university said it was trying to resolve the matter with the pair and was disappointed at the strike.
The dispute is over the sacking of two staff, Helen Ghaly and Sam Bowker, a union official.
"No institution should be allowed to ride roughshod over agreed procedures and violate its employees' rights in this way," says UCU regional official Martyn Moss.
The UCU believes the pair may have been targeted as a result of their role in the union and has also lodged an unemployment tribunal complaint on their behalf.
The union says some 75% of the staff who took part in the ballot voted in favour of the strike.
In a statement, a University of Salford spokesman said: "We have been trying to resolve this dispute with the individuals concerned and are therefore disappointed that a day of strike action has been called.
"We expect all student lectures to run as normal on Thursday.
"We hope that a resolution can be found but, as this is an ongoing legal matter, we are unable to comment further."
Staff at the University of Salford are expected to strike on Thursday in support of two sacked colleagues.