Work to radically transform Union Terrace Gardens is scheduled to start before autumn next year.
The finance, policy and resources committee has agreed to invite firms to bid to carry out the design work for the park.
The committee also approved a proposal to explore options for improving public space in Golden Square and on Schoolhill in the public space outside Robert Gordon’s College.
The work is part of a £2million package of improvements for the wider city centre.
Preliminary design ideas for Union Terrace Gardens drawn up by consultants who produced the city centre masterplan include creating retail units and arts studios within the historic arches, creating an amphitheatre to allow year round events and a pedestrian bridge link that connects Belmont Street with viewing towers and stairs.
Other proposals include refurbishing the existing Victorian toilets and revealing a hidden watercourse.
The proposed projects, which also includes the proposed expansion of Union Terrace Gardens to the north towards Denburn and Woolmanhill, could cost an estimated £17m.
The specialist firm chosen to work up the design will be asked to produce costings and a business case.
If the plans are approved by the council, the work would go out to tender.
Aberdeen City Council leader Councillor Jenny Laing said the design commission could deliver a “transformational regeneration scheme” for Union Terrace Gardens.
She added: “This is not simply about historic restoration of a much-loved Victorian park but the delivery of a contemporary, attractive and active environment for residents, workers and visitors to Aberdeen city centre.
“Union Terrace Gardens is one of Aberdeen’s gems and we want to improve access and usage so everyone can share and enjoy this wonderful space in the very heart of our city.”
A public consultation exercise to gather feedback to gather feedback on the proposals would take place towards the end of this year, with work on the ground scheduled to start before autumn 2017.
The design team is expected to be chosen towards the end of the summer.