Clegg Construction has been awarded the £6.5 million contract to develop the new two-storey building which will replace the existing 1960s SU on its city centre campus
Work is due for completion in February next year with the facility set to open during the spring.
Simon Blackburn, managing director of Nottingham-based Clegg Construction, said: "We're delighted to once again be appointed by Aston University having recently completed the new labs for the Aston Institute of Photonic Technologies.
"This will provide a fantastic new venue for the students' Union."
SU president Reema Quessou added: "This new building will give Aston students the SU they deserve.
"There will be amazing spaces for students to relax and recharge plus we'll have fresh new facilities to transform ambition into reality.